INHALTSVERZEICHNIS_____________________________________________IHM SD
Introduction ........................................................................................................................... 2
Drive 4 WD ......................................................................................................................... 4
Transmission ................................................................................................................................. 5
Hanging up ....................................................................................................................... 6
Brakes ................................................................................................................................ 8
Power steering ......................................................................................................................... 9
Räderund vehicle drive (general references) ......................................................................... 10
Drive system Viscomatic clutch ........................................................................... 11
Hydraulic control circuit ............................................................................................................ 17
Electronic Kontrollanlage ................................................................................................. 22
Funktionsiogik of the system .................................................................................................. 25
Components of the system .................................................................................................... 35
Diagnostics of the system ........................................................................................................ 42
Abs system, version for four drive wheels ................................................................... 43
General description ...................................................................................................... 44
Interference logic for the version 4 WD ........................................................................................ 45
Localization components of the system ............................................................................. 48
Description of function .......................................................................................................... 52
Selbstdiagnose ...................................................................................................................... 53
Electronic engine management Motronic M 3,7 ........................................................ 54
MotronicM3.7 ....................................................................................................................... 58
Operation diagramme ................................................................................................................... 62
Electronic steering box .............................................................................................. 64
Components ........................................................................................................................ 65
Selbstdiagnose ...................................................................................................................... 69
Fuel system circle ................................................................................................... 70
On-board board .............................................................................................................................. 74
Notes/notes ........................................................................................................... 77
1Bi§ B_________________________________________________EINLEITUNG
The available publication documents the variants and the systems, which were specifically developed for the 1B^S. They are to be described here and in the detail represented, thus all necessary information for the general knowledge of the vehicle and the operational principle of the different plants, systems and above all the electronic controls be conveyed can.
The all-wheel drive system Viscomatic, which finds with the new ISA BÖL use, was developed exclusively by the Alfa Rome EO technical designers in co-operation with Steyr Puch.
With 164 was still continued to improve the characteristics of the all-wheel drive owing to „the active " drive system, in which the moment distribution varriert continuously according to the given logics, depending upon driving condition (drive torque, guidance angle, driving speed, process between front axle and rear axle), which are calculated by the electronic steering box VISCOMATIC®.
One received so an all-wheel drive, which gives new 164 high „driving safety " in each driving condition and in the most diverse situations.
The reached advantages can be summarized in such a way:
- To limit „active " interference of the system, which administers the torque process variable, but continuously, without the travelling comfort;
- maximum stability when braking, by a special version of the ABS for 4WD;
- no influence of the drive with driving along curves, due to the construction;
- high achievements of the entire system, due to the good quality of the construction;
- A construction, which made possible it to accomplish an adjustment without large changes at the past model 164 with 2 drive wheels.
4WD propelled
The unpublished construction solution of the drive for *$sk£k the Sl plans a mechanical TRANSMISSION with 6 COURSES. The allocation of the drive over a VISCOMATIC^ clutch with ELECTRONIC CONTROL, as well as a Torsen Diffe
“rential an~cJer Hinteractrse.           -
1. Course: 3.769
2. Course: 2.333
3. Course: 1.680
4. Course: 1.290
5. Course: 1.031
6. Course: 0,837 R. Gang: 3.720
1. Transmission
2. Front differential
3. Reduction gear
4. Drive shaft
5. Universal joint
7. Rear differential Torsen
(The numbers indicate the number of teeth of the different wheel transmissions)
The kinematic pattern plans a VISCOMATIC® clutch between the front axle and the rear axle. The torque between the two wheels is subdivided in front by a conventional differential, while on the rear axle a gate EN differential was used, so that the drive in each situation is maximally used.
Owing to the special construction of the Torsen it makes this kind of self-locking that for differential possible, with small adhesion of a Rades, the drive moment on the wheel with the better road grip too transferred (up to the quadruple value).
With (a new transmission of the company GET-RISE UP with 6 courses begun, that
accordingly one designed, in order to make possible fast accelerations, due to the appropriate gradations of the courses. In this way the maximum torque of the engine (which is very high) is, always at all wheels and in each operating condition available. This results in an unexpected acceleration behavior for a vehicle of this kind with constructional equipment opposite a 2-Radantrieb.
The transmission range contains also the front differential and the drive for the cardan shaft.
Hanging up
The hanging up were again designed, extensive and complex experiments to keep accomplished around a maximum handling and comfort for this 4WD-Fahrzeug. This vote was reached together with the optimization of the specific operating logics of the VISCOMATIC clutch, which are connected in special way with the behavior of the hanging up.
Front suspension
The front suspension became within the range of the position of the steering arm (1) on the hub (2) changed.
In addition all points of the suspension became to the specific sportiven characteristics
the vehicle adapted, thus high guidance precision was reached.
The feathers/springs and shock absorber have a special characteristic. In the shock absorbers are additional feathers/springs, which intervenes in the delimitation phase as an anti-centrifuge and an anti-pitch oscillation function. This makes one possible „softer " measuring of the external feathers/springs for the increase of the travelling comfort.
The applied solutions make possible to adapt the high achievements to the sensitivity of the steering element, with from-following stability in curves, even if border situations
are reached.
Rear suspension
It was completely again designed, in order to ensure the demands of the new drive system.
The new suspension is characterized by the following:
- A lower wishbone (3), which takes up the lateral load;
- An upper unreactive (2);
- A lever (4) and a linkage (5) in longitudinal direction;
- A stabilizer (1), for the entire reconciliation of the group.
The elasticity of the system under transverse loads makes an easy self-steering possible with stabilizing effect.
1. Stabilizer
2. Upper unreactive
3. Lower Schwingarm
4. Semi-trailing arm
5. Linkage
Also at the rear suspension feathers/springs and shock absorbers have specific measuring and the shock absorbers to have an internal feather/spring, like the front.
The applied solutions make as a further improving, and an optimal power transmission at the rear axle in the course for the steering control possible as also in the thrust.
Hanging up with controlled absorption
The electronic Kontroilsystem SCS varied in the measuring of the shock absorbers and is the same system, which already worked with the other versions 164. The interference logic was adapted to the new drive system.
The brake assembly was again developed accordingly for this vehicle and equipped with a specific power steering and ventilated brake disks.
Due to the high demanded achievements the brake pliers were again developed, in order to thus achieve a higher efficiency.
Power steering
The plant of the power steering was adapted to the specific characteristics of this vehicle. The hydraulic guidance pump - propelled by the Poly V belt of the crankshaft - consists of two separated pumps - power steering and Viscomatic -. Both pumps are attached at the same supply cycle. The steering housing is specific, since in this the guidance sensor is, which belongs to the VISCOMATIC system.
1. Hydraulic guidance pump
2. Header tank
3. Zulaufleitungen
4. Steering housing
5. Return pipes
6. Inlet and return pipes VISCOMATIC plant
1B£1 El_________________________________MECHANISCHE GROUPS
Wheels and vehicle drive
With vehicles with all-wheel drive, the automatic work on the wheels and the vehicle towing are problematic, since the two axles must be separated before.
Withis the VISCOMATIC system with an appropriate mechanical
System equipped that complete switching off makes possible for the VISCOMATIC clutch. According to turning the engine (ignition off out) after approximately 4 min. the connection to the rear axle is separated automatically.
Only after this time interval is:
- balancing the individual wheels at the vehicle
- towing the vehicle possible.
Drive system VISCOMATIC clutch
To Alfa Romeobecame between the two axles a Drehmomentverteiler also
electronic control of type VISCOMATIC® assigned, as well as a rear differential type Torsen (basic relationship 4: 1).
With ideal adhesion conditions of the four wheels the drive is made by the front wheels. When revving the wheels up at the front axle, the VISCOMATIC plant distributes the drive torque to the rear axle.
The Kontrollogik takes over the optimal distribution of the torque, that to the rear axle depending upon driving condition is transferred (drive torque, vehicle speed, guidance angle and the slip between in front and in the back).
Electronic steering box control of 9
VISCOMATIC system // ^*W 1Q
Rear gate EN differential
Flange for left half wave
Planetary gear
Group of disk clutch VISCOMATIC
Hydraulic piston for control clutch
Towing protection
Flange for drive shaft
2. 3rd 4. 5th 6. 7th 8.
Signals of the steering box Motronic '“^0
Signals of the steering box ABS “'i/M~reLC
Signal position of the hydraulic piston
Control signal for hydraulic control block
Supply of the hydraulic piston
Hydraulic control block with memory
11. 12.
14. 15.
Supply hydraulic control block (of the hydraulic guidance pump)
OVER EU_____________________________________________VISCOMATIC
The VISCOMATIC® consists of a planetary gear and a viscose rayon clutch with hydraulic control. In addition an appropriate mechanical device makes a switching off for the power transmission possible, which while towing the vehicle on only one axle becomes necessary. - _
1. Towing protection
2. Planetray gear
3. Sun wheel
4. Internal gear
5. Interior disk
6. External disk
7. Piston with hydraulic control
Mixture silicone oil/air
without pressure
transferred torque down
under pressure
transferred torque highly
The torque becomes from the planet pinion cage (1) transferred to the internal gear (2).
The translation from the planet pinion cage to the internal gear is possible, if the sun wheel f3) - connected with the clutch and the brake function - also partly blockieittst. The more largely the blocking, the more largely is the transferred torque.
The viscose rayon clutch (A) consists of lamellas and a mixture of silicone oil and air.
The transmission of the movement in the viscose rayon clutch is reduced by the inconsistency of the oil, since the oil with air vesicles enriched itself. By the piston (4) the oil air mixture rising printing values is suspended, thus reduce the air vesicles, which approach lamellas and it will thus a higher torque transferred.
With the loosening of the clutch by the piston (4) the lamellas are pressed apart with the pressure of warmed up air and the torque which can be transferred reduce.
Each position of the piston, steered of an electrical valve and the respective pressure in the hydraulic system steers thus the torque which can be transferred.
Viscose rayon clutch
The characteristic of the clutch (transferred torque M/speed difference on) can vary inside a certain range (see illustration), that by the condition of the maximum transmission is limited (HARD) and from that the minimum transmission (SOFT). The system places the clutch into a certain point of function in the work area and thus arises the transmission of the necessary torque on the rear axle.
Piston position max.
Piston in resting position
Elimination rear axle
An appropriate mechanical system (towing protection) makes the complete Auschalten and thus the separation of the rear axle for the viscose rayon clutch possible.
That is very important while towing the vehicle on only one axle, since towing with attached axles would damage the VISCOMATIC clutch.
This concerns a mechanical device with hydraulic regulation: The clutch {switch shaft and shift collar) is separated, if the pressure of the tax hydraulic system of the VISCOMATIC sinks under a certain level: The interference value varies depending upon internal friction, temperature etc.: Indikativer value approx. 20 bar.
Switched on clutch switched off clutch
The pressure (p) exceeds Kraft that the applied pressure (p) over cry
Feather/spring (m) and makes a scarf tet Kraft for the feather/spring possible (m) not and those
ten the clutch (G).                                              Clutch (G) is not switched on.
REMARK: When switching the ignition off the hydraulic system needs a certain time (0.5 to 4 minutes), in order to arrive under 20 bar.
Therefore some minutes wait, before the vehicle is towed.
The transmission system plans the use of 4 different liquids, as represented on the following pattern:
Hydraulic control circuit
A hydraulic system with high pressure supplies an accumulator, which leads the necessary liquid quantity with a sufficient pressure to the hydraulic system. The supply circle is integrated, and by means of a pump by the crankshaft is propelled with that the power steering. This concerns a double pump with 2 different pressure levels for the two circles:
1. max. 100 bar vane-type pump for the hydraulic guidance circle and
2. max. 200 bar - piston pump for the VISCOMATIC circle.
1. Ausgleichsbehäiter
2. Double pump
3. Housing power steering
4. Accumulator with hydraulic control block VISCOMATIC
Hydraulic pattern
A = hydraulic control block B = VISCOMATIC clutch
(*) von/zu hydraulic guidance circle
Engine supply pump
9. 10.
Relief valve ~G-££*~~t ** ■ " return non-return valve
Header tank with Filterelement
Pressure filter cartridge
Sensor oil level
Return non-return valve
6. 7th 8.
Electronic steering box VISCOMATIC
Pressure sensor proportional valve flow control
14. 15. 16. 17.
Memory load valve
Piston attitude VISCOMATIC
Automatic bleed valve
Towing protection
Auxiliary filter
u~ 7h At& -2 7 ** Uf^Ur
Description of function
The supply pump (2), propelled by the Poly V belt of the engine (1), the liquid leads to the hydraulic guidance plant and to the hydraulic control block of the VISCOMATIC (A). The header tank (3) with Filterelement in the oil return the reconciliation of the quantity varying of the oil, which arises during the enterprise, guarantees due to the work quantity (of memory) and the thermal extension: Altogether approx. 400 cm3. The sensor (4) the electronic steering box informs VISCOMATIC (5) in case of of low oil level. The electrical valve at the accumulator (13) becomes from the steering box (5) activated and loads the memory (6) up, whereby a pressure between 82 and 95 bar of a sensor (7) is held. The memory (6) - capacity 0.5 dm3 - the necessary energy for the enterprise of the VISCOMATIC guarantees inside the system; on the supply line a pressure filter (11) is - filter achievement 20 u.m - that the whole group before foreign particles protects, which could damage the valves, as well as a return non-return valve (12) that to the pump prevents the return flow of the oil; a further auxiliary filter (17) protects the memory load valve (13). The valve (9) the system protects against positive pressure and opens the circle at 110 bar. The return non-return valve (10) return flow prevents into the VISCOMATIC group by the hydraulic guidance circle.
The proportional valve for adjustment (8) steer the VISCOMATIC clutch (B) and regulate the oil flow in the chamber (I) of the piston (14); the oil pressure in the chamber (II) constantly by the memory one maintains: therefore becomes on varying the quantity led into the chamber (I) shifting the piston and thus varying the stiffness of the clutch reached. The function of the valve follows in the detail:
A. Valve with a certain electric current supplies: Liquid quantity to the chamber (I) of the piston
b: closed valve
C: Discharge the chamber (I) from the piston to the container - with started engine -
D: Discharge the chamber (I) of the piston - with turned off engine: It becomes a further river the oil reservoir in the memory (6) and in the chamber (II) reached, so that the whole plant is emptied.
The pressure in the chamber (II) switching on of the clutch (towing protection on 16 controls): If the pressure sinks, scolded the clutch mechanically the whole group of clutch rear differential out.
The valve (15) - calibrated on 102 bar - for the automatic exhaust of the plant one uses (for further details see „exhaust of the circle ").
; &g&, &*rw^
Supply pump
1. Pump (A)
Vane-type pump (from aluminum)
Number of revolutions 500 1/min max. 7500 1/min
Quantity of 7 4 - 9 + 0.8 l/min.
max. pressure 100 bar
2. Pump (B)
Piston pump (from casting)
1,4-^rr l/min. mixes 2000 1/min at number of revolutions
max. pressure 200 bar
iköl: TUTELA Gl/R
Hydraulic control block
In a building group all valves and components of the hydraulic system are accommodated for the controlling of the VISCOMATIC clutch.
1. Accumulator
2. Pressure sensor
3. Speicherladeyentil
4. Hydraulics proportional valve
5. Pressure filter cartridge
6. Return non-return valve
7. Return non-return valve
8. Relief valve
9. Auxiliary filter
VISCOMATIC_________________________________________________IBÖ SSI
Exhaust of the hydraulic system VISCOMATIC
The exhaust of the circle is made by an appropriate valve inside the device, and is not thus not accessible and not adjustable.
The exhaust is to be accomplished only with ALFA ROMEO the TESTER: This procedure plans the start of the engine, whereby this is brought to 2000 revolutions; then sends a controlling of the tester a constant river of 450 mA to the proportional valve and controls according to also the memory load valve, increases the pressure of the circle over the maximum operating values, whereby the bleed valve is opened (on 102 bar calibrated) and lets to the container air collected in the plant to stream out. In the case of completion of this procedure it is possible to examine with the tester whether the plant without air is.
Electronic Kontrollanlage
The electronic steering box VISCOMATIC controls „the slip " between the foremost and rear axle and limits it at certain values, depending upon the different driving conditions. These conditions are inferred by several sensors or taken up by other plants (ABS or Motronic). The steering box steers therefore the valves, which regulate the function of the viscose rayon clutch. The operation diagramme points this out schematically:
Sensors and Kontroilogistik
The Kontrollogistik of the steering box, which steers the hydraulic system of the VISCOMATIC, plans the availability of a series of data, which are inferred partly directly by sensors and are partly again-processed. In accordance with these parameters the steering box regulates the electrical valve (20) with a variable river (from 400 to 2300 mA) proportional for the speed of the piston, the connection of the clutch varied and thus the allocation of the transmission moment on the rear axle.
The directly inferred data are the following:
- The number of revolutions of the four wheels. The four data become from the abs system (1) taken over.
- The Drehzahi of the engine by the steering box Motronic (7).
- The opening angle of the butterfly valve (in the percentage), by the steering box Motronic (5).
- The guidance angle (6), given by a specific sensor in the steering element housing.
- The position of the piston (2), whose stroke from 0 to 5 mm can vary; the position of maximum resetting is recognized, if the river of the electrical valve (20) is with 900 mA.
- The pressure of the hydraulic system of the memory, measured of the sensor (8); this pressure is held between 82 and 95 bar by a memory load valve (22).
- A signal during operation of the brake (3).
- A signal when switching on of the reverse gear (4) on.
- Sensor oil level (9).
1B^1 SO” _________________________________________________VISCOMATIC
The system is with a control light (21) and with the possibility for the diagnosis with the Alfa Romeo tester (10) equipped.
REMARK: The function of the steering box is dependently on the voltage level of the battery, under 9 V scolded themselves it not.
There are parameters, which are not inferred directly by the sensors, but by the steering box in accordance with special logics to be calculated, which are described as follows:
Function logic of the system
The most important logics are described here, which are regulated by the software of the steering box, in order to regulate the allocation of the torque by the clutch.
Drive torque
The drive torque at the wheels is calculated by the product of the torque, which is delivered by the engine for the entire drive. It is indicated as percentage of its maximum value. The torque delivered by the engine is inferred from the curves of the load diagram, which is stored in the steering box. Each value of the number of revolutions and percentage of the butterfly valve opening, correspond to a value of the torque, which is delivered by the engine.
The total drive is calculated against it by the relationship between engine number of revolutions and number of revolutions of the front axle.
0                               1000                            2000                             3000                           4000                            5000                            6000                            7000
Slip between foremost and rear axle
By slip one understands the proportional difference of the speed of the front axle opposite the rear axle.
Front axle - rear axle x 100
Slip = speed difference -------------------------------------------------
Rear axle
In order to be able to have the value of the slip due to revving the tires up, one must take the kinetic slip.
This kinematic slip is the result of the over each other setting of the two conditions:
First is due to the variability between the turning extent of the tires due to for example wrong printing values, or different wear condition, unequal tire load, presence of the spare wheel etc.
The second condition, which determines the kinematic slip, is the different rotating speed of the axles, which arises in the curve. The C.I.R. (center of the momentary turn) shifts depending upon guidance angle, in addition, depending upon deviation of the tires.
Deviation of a Rads with tires under a lateral load.
This angle results from different variables, how: Kind of tire, pressure of the tire, trap coefficient.
In addition it is directly proportional to the centrifugal energy (square of the radius speed, guidance radius and measures of the vehicle) and the torque used at the wheel; it is opposite proportional against it to the vertical load on the wheel.
The steering box regards only the kinematic effects and thus only the speed parameters and guidance angles.
- With standard speed the speed increase increases the deviation forward. That calls (see illustration) a shifting „of the center of the turn " (+) forwards, with from-following reduction of the kinematic slip.
On the other hand the situation turned around when backing up: Shifting „the center of the turn " (+) causes an increase of the kinematic slip.
There are tables over the normal trip and over the reverse movement. The kinematic slip is reduced as described with increase of the deviation (standard speed) and with reverse movement the slip increases.
The evaluation of the kinematic slip due to the curve movement is read from the system, and compared with the stored tables in the program of the steering box - in that the important data are contained -.
Positioning the piston
In order to guarantee that the distribution of the course torque on the two axles is made in shortest time it is before-shifted, the regulation, as the piston is positioned depending upon course torque. From this position one proceeds, in order to make the definite attitude concerning the slip, if this arises.
In order to guarantee a good function of the system, for example when fast starting, with which the taken values of the important parameters close the piston during pre-setting, other signals are not considered, which would cause mismatching partial openings of the piston. If the system would consider for example small guidance angles at low speeds, the piston is opened, whereby thereby disturbing conditions would arise when driving.
Attitude of the course slip
With special circumstances the system does not intervene also at important slip values.
For example a high slip value is certified at low speeds. One avoids in such a way that the attitude of small measuring errors of the speed and irregularity of the road surfacing, although small, is affected, which would be important however in this case.
For the same reason the certified slip value increases, if the course torque is limited.
Attitude of the transverse slip of the rear axle
The closing differential (Torsen 4: 1) in the rear axle causes that in the curve the internal rear wheel is loaded with a quadruple higher torque. This wheel tends to revving up, since in the curve also the vertical load sinks. In this condition the slip between the two axles to inappropriate way and the piston reduce tended to open and lead to an allocation of the torque between the two axles with increase of the average speed of the rear wheels, which brings driving difficulties with itself. In this case a function intervenes, which adds itself to the difference between the real slip and the certified and is lost due to revving the internal rear wheel up. Therefore the piston remains closed due to the signal by this wheel, whereby the movability of the vehicle is improved.
Attitude of the sliding operating slip
With sliding enterprise the exhaust brake works the vertical load on the rear axle, which can rev up therefore easily particularly on the front axle, on the other side sinks in this condition.
REMARK: If the speed of the rear axle more highly than those the foremost
axle is, takes the slip negative values.
The certified negative slip at low speeds is therefore for the same reasons higher, from those, as seen, at low speeds the course slip is high. At medium speeds the value of the certified slip is limited, since a good torque value reduces the Untersteuern (with bad adhesion), which arises in the curve particularly on the front axle on the rear axle.
At high speeds the threshold increases strongly, in order to let the exhaust brake affect only the front axle and to thus guarantee a good driving stability.
Attitude when braking
The system refers to the rear axle. When braking the real speed of the rear axle is not considered, if this by a delay over 0,24 g is determined. At higher delay values the datum speed sinks not in accordance with the real process separates gradually.
The VISCOMATIC normally intervenes, until the difference between the effective speed and the delimitation speed does not exceed a certain threshold value (also function of the guidance angle: This threshold is limited with low guidance angles). Above this threshold the VISCOMATIC does not intervene during braking, except with exceptions, whereby malfunctions with the abs plant are avoided (for further details see „brake system ABS 4WD ").
r \ 3
Description of function
The system of the VISCOMATIC is administered by the controller N 75.
The permanent voltage supply of the controller is made via the battery, by the protection F1 (7.5 A) - additional fuse housing G 2 -, on the controller pin 1.
Against the pins rests 20 and 25 of the controller measure. The information „ignition " comes over the protection F 4 (3 A) - G 2 - on the controller pin 14.
The main supply for the controller is made over the change relay 1104.
Relay function: no Fehler>
with Fehler> the sensors:
After the info. „ignition " over pin 14 at the controller, this accomplishes a Eigendiagnose
Relay becomes over the Kl. and supplies now the controller excites 86 with 12 V via Kl. 30 over Kl. 87, protection F 5 (10 A) - G 2 - at pin 13 with battery voltage.
Indicator light becomes of relays Kl. 87a with tension supplies and shines.
Guidance protractor L 53
1 = 5 V
2 = signal voltage - > pin 3 Stg
3 = measures
Oil pressure sensor L 56
A = measures of B = 5 V
C = signal voltage
Pin 18 Stg
Sensor plunger lift L 55
Pin 1 = 5 V - ►
Pin 2 = signal voltage - *■ pin 16 Stg
Pin 3 = measures
Sensor oil level L 54 schlioßt with small oil level and informs with a measure signal the controller at pin 6th FF ** - * “** approx. H? tc *?
Switch reverse gear: H 2 informs the controller at pin 10 with 12 V that the reverse gear is inserted.
Brake pedal switch H 3
1 =12 volt
2 = pedal pressed - *■ pin 23 Stg “h| 4 = pedal not pressed - ► pin 22 Stg
Except of the appropriate sensors, the steering box receives N75 information from the abs system and Motronic system: The pins 7.8.9 and 21 of the N75 are connected with the steering box ABS N51, from which they receive proportional signals for the speed of the 4 wheels; at the pins 15 and 12 comes against it from the steering box Motronic S11 the signals of the butterfly valve angle and the engine number of revolutions.
The logic before shown processes the steering box the control signals of the actuators, which are controlled accordingly: From the pin 11 the signal “Duty Cicle” (variable, 250 cycles per second) comes, which the proportional valve inside the hydraulic control block M25 steers, of the pin 24 comes a continuous signal 12 V to the controlling (ON OFF) of the memory load valve of the group of M25.
Pin 4 and 5 for the diagnostic possibility (plug T1) - line K and L - to the connection with Alfa Romeo the TESTER. Pin 19 12 a V-signal for the control light of on-board board C10 in case of of stored disturbances.
Components of the system
Electronic steering box (N75)
It is under the middle console, in the shown position:
PIN-OUT steering box:
12 V-supply battery
Agreement at safety external switch (12 V)
Signal guidance angle
Diagnostics line “K”
Diagnostics line “L”
Signal oil level (5 V)
Signal speed wheel in front rh (of ABS)
Signal speed wheel rear. rh (of ABS)
Signal speed wheel rear. left (of ABS)
Signal switched on reverse gear
(12 V)
Control signal proportional valve (Duty Cicie)
Signal Mptorendrehzahl (of Motronic)
12 V-supply of safety external switch
12 V-supply (+15)
Signal butterfly valve angle (of Motronic)
Signal plunger lift
Supply + 5 V for the sensors
Signal pressure hydraulic system
Signal for signal lamp on-board board (12 V)
Measures of achievement circles
Signal speed wheel in front left (of ABS)
Signal released brake pedal
(12 V)
Signal pressed brake pedal (12 V)
Signal control memory load valve (12V)
Measures of system circles
Safety external switch (1104)
The steering box controls and regulates the supply of the achievement circles by an appropriate external switch, which interrupts the supply at the actuators and thus the system switches off, if it comes to disturbances.
The external switch is on the right side behind the combination instrument.
1104 safety external switches for steering boxes VISCOMATIC
Stop light switch (H3)
The same switch as for is the circle of the stop lights, 2 signals by the controller is processed: approved and pressed brake pedal.
Reverse gear switch (H2)
The same switch as for is the circle of the backup lights, from which from the signal of the switched on reverse gear proceeds.
Sensor oil level (L54)
It is on the expansion tank for the hydraulic guidance plant and VISCOMATIC (for further details see “power steering”).
1. Sensor
2. Float
This concerns a switch (N.C), which is connected with a float, that opens it, if the level of liquid the “MIN” - value reaches.
Sensor plunger lift (L55)
The sensor is in the VISCOMATIC group and is bound with a linkage at the pistons. This concerns potentiometer, that the steering box a signal proportionally to the position of the piston sends (supply voltage 5V, Rmax 2 kΩ).
1. Sensor plunger lift
The measuring of this sensor takes place automatically: Each time, if the attitude valve at minimum value (< 900 mA) stays a certain time long, this reference value is taken as 0-Weg, while the final stroke of the piston is accepted as maximum way (5 mm).
Sensor guidance angle (L53)
This concerns potentiometers, which is accommodated in the steering housing. It sends a proportional signal to the steering box to the guidance angle (sign „+ " steering angle right, signs „- “steering angle left).
- Supply voltage = 5 V
- Rmax = 1 kß
- Range guidance angle = 330° (+ 3%)
1. Steering housing
2. Sensor
Measuring of the sensor
- The vehicle with wheels on straightforward and steering wheel position - to GUIDANCES FOR the REPAIR see microfiche
- The sensor into the steering housing do not build, which plugs attach.
- Attach ALFA ROMEO the TESTER to the steering box VISCOMATIC.
- The key to trip set and with the tester examine that the tension of the output signal of the sensor is with approx. 2,5 V: If the tension should be approx. 0 V, that
Element of the sensor around 180° turn.
It fastens the sensor on the steering housing, makes certain that the steering element stands in the position guidance center and is the tension signal with 2.5 ± 0,04 V.
- The correct function examined, as the steering wheel is turned and at the right attack is kept two seconds long, then likewise at the left attack and with the tester to examine that no error is indicated.
Electrical valve hydraulic control block (M25)
In the hydraulic control block (see hydraulic control circuit) are two electrical valves, which are steered by the electronic steering box.
1. Hydraulic proportional valve
2. Memory load valve
3. Memory
Memory load valve
This concerns a valve ON/COFF that supplies the memory and holds the pressure between 82 and 95 bar, during the normal enterprise of the vehicle.
NOTE: The valve is only also activated at engine number of revolutions over 400 rpm and at speeds over approx. 4 km/h.
Proportional valve river attitude
This concerns a servo valve that a liquid quantity proportional to the excitation stream lets flow through. In this way the Kolbenkammer with the transfer of the piston is varied. The signal that the steering box sends to this electrical valve is a variable “Duty Cicle” (12 V, max. 2.3 A) - see illustration.
With a direct supply (12 V) the valve was damaged, therefore the system interrupts the supply, if this tension continues continuously longer than 100 ms.
Characteristic curve of the valve
With a certain river at the electrical valve one achieves a certain liquid quantity, which the pistons from a position to the other one transferred and so the translation about a certain representation with one „talk " slip to another with one „desired " slip brings, which was calculated by the steering box.
Excitation stream (mA)
Diagnostics of the system
A complex self diagnostic logic controls the complete system in each moment:
- Supplies of the circles of the system and the achievement circles
- Examination of the internal memory (only with the initial test).
- Examination of the detailed signals (range of the certified values, stages of varying and plausibility) analogisch, as digital.
- Examination of the control signals of the actuators.
If an error or a disturbance is present, this information - by an appropriate “error code” - is transmitted to the error memory (RAM) of the steering box; at the same time the disturbance signal lamp on on-board board lights up and the fail-safe program is activated.
More than 70 different error codes can be inferred!
The disturbance signal lamp on on-board board shines for 1 -2 seconds when starting during the initial at the beginning of the system on {storages and internal components).
If no errors arise, expire them, if the controller infers against it errors, remains the signal lamp on.
The fail-safe program depends on the taken error: If an error arises with a sensor, which does not affect the whole system completely, the signal value is corrected this sensor with a reference value („Recovery ").
If against it an important disturbance of the system is inferred, like for example at the hydraulic system, the system becomes cut out. If the errors in addition the achievement circle concern scolded the steering box with the safety external switch the system out.
All stored Fehler-die „current " as well as „the previous " can only with the Alfa
Romeo tester to be read and deleted.
In order to delete and the fail-safe program switch the signal lamp off, it is sufficient to switch the steering box off (keys on STOP). If during restarting the errors is no longer present, the signal lamp does not light up any longer and the fail-safe program is not activated. The before taken up error remains nevertheless stored.
For each error code a speedometer is intended: With the occurrence of an error this counter is placed to its maximum value (255): With each restart the counter is lowered around 1, if the error is no longer present; In this way an error is cleared after 255 restarts, if it arose coincidentally and does not occur any longer, from the memory.
Likewise the delete operation brings all counters to Rome EO testers with the ALFA zero,
General description „ABS "
The 164 4x4 is equipped with the electronic anti-skid system (ABS). This concerns a specific version for this vehicle with all-wheel drive. VERSION with 6 sensors and 4 channels.
Speed sensors
The four sensors, which are assigned at the four wheels, indicate the respective wheel speeds to the electronic steering box - they were again designed.
Sensors of the crosswise and longitudinal acceleration
These two sensors were added, in order to infer additional parameters, which are needed by the specific Kontrollogik the braking. This concerns electromechanical devices, which are led during accelerations (+) to react and their value to the electronic steering box.
REMARK: In the previous versions these sensors were simple on off switches. In this case it bargains for around hall effect sensors,
proportional signal to the taken speed pass on: Makes possible for the operating logic to activate different behaviors depending upon acceleration borders, while before only one interference threshold could be considered.
Clutch switch
Makes possible the information to the steering box over the interrupted force river between engine and transmission, in order to be able to correct according to the braking in this condition.
Function high-speed no-load operation (LDA)
ABS is in connection with the MOTRON IC system. When strong decelerations the vehicle and on the basis of high engine speeds, due to the drive system the engine would tend when braking to turning off. The steering box ABS informs the steering box in this case MOTRONIC. In addition the engine brake effect became effective also at the rear wheels, which would brake more than necessarily. For the avoidance of the over braking of the rear wheels, the logic of the system seizes „opening of the no-load operation automatic controller ".
Signals for the VISCOMATIC system
The steering box ABS sends the 4 Geschwindigkeitssignale of the wheels to the VISCÖMAT system, which uses these information, in order the drive logic to define (see system VISCOMATIC).
Interference logic for the version 4x4
With the special version „" the ABS all conventional interference logics receives 4 x 4 from the brake system, in order to prevent the blocking of the wheels.
The presence of two additional sensors (the two accelerometers) has the development of other specific logics for 4 x 4-Fahrzeuge “ÜÜrffl (§3* in particular made possible.
1. Different adhesion of the wheels
In case of of different detention condition between the right and left side of the vehicle (e.g. layer of ice…), a different reaction at the ground at both sides arises: From it results one M-moment, which is called „craving " and which brings vehicle to the rotation around the point „M ".
With vehicles with only two drive wheels this disturbance can be reduced easily by the conventional abs system, the brake pressure accordingly modulated and in particular at the demanded drive wheel reduced, as well as owing to the function „SELECT low " (clocked controls at the rear wheels). A drastic reduction of the yaw moment makes M. possible.
'* €Zp&>®*me*'%
With vehicles with four drive wheels craving is strengthened by the larger reaction of the two responsible wheels, caused in the special by the viscous drive of the rear wheels: From this an increase of the yaw moment M takes place in relation to the versions with front wheel drive.
The specific logic of the ABS intervenes thus, as the increase of the pressure on the wheels is affected with higher adhesion, and so the yaw moment value M is strongly reduced. Thus driving safety of the vehicle is improved, in the case of the different adhesion between the two sides of the vehicle.
2. Curves with high speed (also with good adhesion)
The Kontrollogik of transverse acceleration intervenes, if the sensors infer different speed between the wheels of the two sides, however impossible in case of a curve with high speed. The vehicle would override, since the ABS would lower the pressure in the two outer wheels too strongly. The reduction of the yaw moment M would let the over-regulation effect M become stronger, also with easy brakings.
ABS----------------------------------------------------------------------------------\ imm &u
The sensor of transverse acceleration indicates the actual situation to the steering box, which leads a certain brake pressure, above all to the rear. In addition the abs function is ahead-sent „", which intervenes and in advance „releases the brake pressure ".
3. Bad adhesion with acceleration (or in the sliding enterprise)
For example when driving a curve out with bad adhesion all four wheels have a certain slip. The datum speed value, which is normally calculated, is very inaccurate and causes for one „release effect " of the brake printing with from-following adhesion problem. This value is thus corrected, as acceleration or slowing down of the sensor longitudinal acceleration is measured. One reaches so a braking with limited slip.
4. Snaps minimum number of revolutions (high-speed no-load operation)
With vehicles with four drive wheels, a delay of the rear wheels when braking or when simple slowing down due to the engine brake, which brake from-following more than necessarily „", increases. This situation is strengthened only partially by the VISCOMATIC clutch. The clutch remains closed in some cases „" and leads a certain torque to the rear range (for further details see „VISCOMATIC "). With bad adhesion, this problem solves the function „high-speed no-load operation ", which eliminates the effect of the engine brake at the wheels. The sensor of the longitudinal acceleration infers the range of the slowing down and with bad adhesion (it intervenes the ABS), sends it a signal, „from LDA ", to the steering box of the Motronic that the number of revolutions amends or lets the engine „more softly " to the idling speed come.
REMARK this function however interrupted:
- pressed clutch pedal (situation by the appropriate switch on the clutch pedal one takes).
- Speed of the vehicle too small
- Engine speed already with minimum value (no-load operation)
Localization components of the system
1. Inductive sensors vehicle speed 4.
2. Clay/tone wheels 5.
3. Hydraulic group with abs tax
housing 6.
Control light
Sensors along and transverse acceleration
Switch clutch pedal
Hydraulic's group with steering box ABS
This concerns the same building group („hybrid "), which was already installed in 164 the super. In a block the electronic steering box with hydraulic's group and 4 electrical control valves for the individual wheels.
PIN-OUT steering box; Plug „A " (G273)
1 2 3
Signal lamp disturbance
Switch brake pedal sensor longitudinal acceleration
4. -
5. Switch clutch pedal
6. Signal rear wheel left for VISCOMATIC
7. Signal front wheel left for VISCOMATIC
8. Signal front wheel left (measures)
9. Signal rear wheel left.
10. Signal front wheel rh (measures)
11. Supply for sensors acceleration
12. Signal front wheel rh.
13. Measures for sensors acceleration
14. Sensor transverse acceleration
15. Diagnostics line K
16. Diagnostics line L 17. --
18. Signal front wheel rh for VISCOMATIC
19. Signal rear wheel rh for VISCOMATIC
20. Signal front wheel left.
21. Signal rear wheel left (measures)
22. Signal rear wheel rh (measures)
23. Signal rear wheel rh 24. “
25. Signal LDA to the Motronic
PIN-OUT hydraulic's group: Plug „B " (G272)
1. Supply (with 10 A-protection) Kl. 15
2. Direct supply of battery
3. Measures
4. Signal lamp disturbance
Ground connection „C " (G275)
Sensors speed
The four sensors are on the hubs of the four wheels in the range of the clay/tone wheels - 44 teeth -. The sensors were again designed.
Air gap value between wheel and sensor:
Air gap for front wheels air gap for rear wheels
T = 0.55 - p 1.2 mm T = 0.6 f1,3mm
Clutch switch
This concerns a double N.C. - Switch (closed), which opens, if the clutch pedal is pressed.
Parallel to the contact a resistance (R = 4.22 kß) is, which serves for the examination of the electric circuit.
Electrical pattern
pin 1 not attached
pin 2 not attached
pin 3 measures
pin 4 signal under tension to the steering box
closed contact < 1.25 V
opened contact > 1.25 V
< 3.00 V
separated switch > 3.00 V
< 4.50 V
abs____________________________. ----------------------wmrn m^
Sensors acceleration (crosswise and lengthwise)
This concerns electromechanical devices with the principle of the measures/feather/spring: An acceleration moves the measures, which act against the feather/spring, whose movement is inferred by a magnet and by an element with hall effect is processed, which emits a tension signal corresponding for taken acceleration. The two, sensors are under the center console, in the proximity of the Barizentrums of the vehicle.
Electrical pattern
pin 1 measure
to pin 2 output signal (under tension), see diagram
pin 3 supply (5 V)
REMARK: The two sensors are calibrated in the structure equal as well as on the same values: The steering box processes the input values differently, which arrive at the two pins.
In addition the transverse sensor has an arrow, which shows in driving direction of the vehicle.
A. Measures
b. Feather/spring
The sensors contain a magnetic element. Therefore special caution, if in the proximity with iron-magnetic material one works.
Description of function
The system is administered and steered by an electronic steering box, which is positioned inside the hydraulic's group of N51.
The activation in the circle of the brake assembly is realized by the hydraulic's group of N51, which control the pressure of the brake fluid after controlling of the electronic steering box; it contains the electrical pump as well as the four electrical valves, one of the brake fluid with the respective external switch for each wheel (so-called „4 channel 'version) with respective external switch.
The supply of the system is made directly from the battery and by ignition via the protection of the specific protection G125 (10A).
The four sensors on the wheels L28, L29, L30 and L31, are connected with the steering box and send a signal proportionally to the speed.
The two acceleration sensors N62 and N63, supplied at the pin 3 with 5 V and measures of the pin a 1, supply a proportional signal for taken acceleration, which is handed over to the steering box to the pin with 2.
By the signal of the switch the information about an arising braking is given to the brake H3, which steers the stop lights.
The clutch switch H21 is directly connected with the steering box and sends a tension signal, which informs engine and transmission about the separation. The steering box is connected (pin 25) with the Motronicsteuergerät S11, to which the demand is given to the accelerated minimum number of revolutions (LDA).
LDA = idling speed rise = high-speed no-load operation.
In addition a connection with the controller N75 Viscomatic exists for the transmission
the Geschwindigkeitssignale of the four wheels.
The internal self diagnostic system in the steering box announces disturbances or not correct function over pin 1 to the appropriate signal lamp of on-board board C10; the same signal is announced also to errors in the hydraulic's group - pin 4 of the plug G272 -.
abs_____________________________________________jiöö m
Same diagnosis
The available version of the ABS excludes the normal brake system from the Selbstdiagnose, which holds continuously all components and parameters of the system under control: in case of of disturbances or bad function scolded yourself the system automatically out and only the conventional mechanical servo-supported system is active. This situation is indicated to the driver by an appropriate signal lamp of on-board board. The signal lamp „disturbance ABS " is activated with switched on ignition - its expiring secures that the initial test test of the system was positive and is present no disturbances.
5 6 7 8 9 10 11
1B^L GH___________________________________________MOTRONIC M 3.7
Electronic engine management Motronic M 3.7
A new electronic engine management steers and supervises all parameters of the engine, optimizes achievement and consumption by fast responding in the different operating conditions.
This concerns the version M 3,7 of the examined and reliable system BOSCH MOTRONIC.
The new Motronicsystem M 3,7 equipped with a controller of the newest technological development.
The electronic ignition with „static distribution " was changed, with one coil each for each spark plug (MONO COIL); in addition the achievement modules are contained inside the steering box; this solution eliminates the external ignition circle, and increases thus the reliability and the security of the ignition system.
With this version M 3,7 a phase injection (sequential) for each cylinder was realized. The injection moment is not alike to no more for all cylinders, for each cylinder takes place this at the optimal point of injection, which is calculated by the steering box, depending upon load, number of revolutions and engine temperature.
The moment planned in the calculation is the injection, from which the duration of injection is calculated. This is the thermodynamic point and its correct control makes possible a still more exact optimization of the engine run. The system activates also a correction of the duration of injection.
1. Electrical injection nozzle \|/
2. Mono coil 2
With new concept and Design „debit meter " (air mass measurer) is, with „warmed up layer ". This new air mass measurer does not contain as with the previous version „with flap " the sensor of the sucked in air temperature; with this version this sensor is separately attached before the debit meter.
1. Sensor air temperature
2. debit meters - air mass measurers
The phase sensor was changed (sensor cam angle): It concerns no longer around a sensor with magnetic induction, but a sensor with hall effect.
1. Sensor cam angle
The number of revolutions and reference mark sensor at the front wheel remain unchanged.
The exhaust system consists of two separated systems (front and rear Zylinderreihe)
with ever a catalyst and with ever an upstream Lambda probe (1 and 2).
Before the two separate main catalysts is in each case a Vorkatalysator (3).
The two same probes, send a signal to the steering box over the remainder oxygen quantity in the exhaust gas, everyone concerning the Zylinderreihe. The steering box changes the mixing proportion for the appropriate Zylinderreihe.
This solution makes a refinement „for Lambda control possible ", which considers the differences between the different cylinders, with from-following improving of the exhaust gases and a reduction of the fuel consumption.
1. Lambda probe front Zyiinderreihe (cylinder No. 4; 5; 6)
2. Lambda probe rear Zylinderreihe (cylinder No. 1; 2; 3)
3. Vorkatalysator
Function „LDA " (idling speed rise)
In connection with the steering box ABS, activate the Motronic system the so-called LDA logic, i.e. the waste curve of the engine speed without load is made in the form of steps (accelerotor pedal fast approved with engine with high number of revolutions).
Speed „v "
A = brake beginning t = response time
* with LDA ** without LDA
Time „t "
The information idling speed becomes also to the controller of the Viscomatic
passed on and evaluated.
Control empty run govern (signal PWM)
Operation diagramme injection and ignition system
Lambda probes
Air cleaner
Plug connection for ABS
Plug connection air conditioning system
Admission for diagnosis system
(Alfa Romeo tester)
Igniting and injection steering box (Motronic)
Plug connection Viscomatic
Knock sensors
Temperature sensor coolant (NTC)
Sensor number of revolutions and reference mark
Automatic controller fuel printing
Air mass measurer
Potentiometer butterfly valve
16.    Temperature sensor sucked in air
17.    Butterfly valve body
18.    Actuator constant minimum number of revolutions (no-load operation)
19.    Oil steaming racer
20.    Pulsationsdämpfer
21.    Cam shaft sensor
22.    Spark plugs
23.    Ignition coils
24.    Electrical injection nozzles
25.    Electrical evaporation valve (coal active container)
26.    Fuel filter
27.    Electrical fuel pump
28.    Fuel tank
29.    Relay group
Electronic steering box
External switch gasoline pump
Exit signal
Actuator minimum number of revolutions (opened)
Vehicle speed
Electrical injection nozzle, cylinder No. 1
Number of revolutions sensor
Electrical injection nozzle, cylinder No. 2
Sensor cam shaft
Electrical injection nozzle, cylinder No. 3
Exit signal engine number of revolutions
Measures of injection nozzles
Relay air-conditioning system
Measures of Lambda probe 2
Ignition cylinder No. 6
Measures of Lambda probe 1
Ignition cylinder No. 5
Signal Lambda probe 1
Ignition cylinder No. 4
Signal Lambda probe 2
Supply (by external switches
R measures measures for air masses
Number of revolutions sensor
Measures for ignition
Ignition cylinder No. 3
Supply over ignition
Ignition cylinder No. 2
Exit supply 5 V
Ignition cylinder No. 1
Signal air-conditioning system
Supply (battery)
Signal air-conditioning system (compressor)
Agreement supply
Signal for alarm installation
(at external switch Motronic)
Knocking sensor 2
Electronic measures
Knocking sensor 1
(Screen sensors)
Measures for knocking sensors
Actuator minimum number of revolutions (closed)
Absolute dimensions for sensors
Electrical injection nozzle, cylinder No. 4
Signal butterfly valve angle
Electrical injection nozzle, cylinder No. 5
Sensor air temperature
Electrical injection nozzle, cylinder No. 6
Sensor water temperature
Signal LDA (of abs steering box)
Electrical evaporation valve
Diagnostics, line L
The electronic steering box receives the signals from the sensors, which read, process the function of the engine „" them after one inside „the briefcases " stored logic, which connect among themselves optimally the different parameters, and from-following the actuators activates, so that the engine always functions with maximum achievement and uniformity.
Here the new and/or different components are described in relation to the previous version M 1,7
Air mass measurer (S5)
Operational principle air mass measurement
The heated surface is regulated on a constant temperature rise to sucked in air. The moving by intake air cools and changes thereby the resistance of the heated surface (PTC behavior). The filament current is thereby the measure for sucked in air mass.
1. Plug
2. Measuring channel
3. Sensor with warmed up layer
A = air entrance
The measured river is proportional to sucked in air mass.
The air mass measurer determines directly air mass (and not the quantity as with the previous versions with amount of air measurer).
pin 1 - Measures pin 2 - absolute dimensions pin 3 - supply 12 V pin 4-Meß-Signal
A = air
R-S = sensor with warm layer
River, which flows by R-S
Quantity (kg/h)
River (A)
12 3 4
RH = heating resistor affects thermally R-S
R-S = sensor resistance
G 1 = compensation resistance
Blank = air temperature feeler resistance
m = quantity (kg/h)
U = tension between pin 4 and 2
U [v]
The correct enterprise of the air mass measurer depends on the condition of the air cleaner, which must be examined therefore regularly.
Sensor cam shaft (S 52)
The phase sensor (sensor cam shaft) consists of a device with hall effect.
Electrical pattern
Pin 1 = supply pin 2 = exit signal pin 3 = measures
The tension signal (as) forms, if the pin goes past from the cam shaft at the sensor.                r v
Air gap T = 0.1 - 1.5 mm
Lambda probe (S 35a and S 35b)
The two Lambda probes are from the same design, as they are used also with the previous versions.
Sensor air temperature (S 34)
The sensor for the sucked in air temperature is separate with this version from the air mass measurer. This concerns a NTC sensor.
Electrical pattern
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Mono ignition coil (A8)
Each individual ignition coil on the cylinder heads, supplies directly a spark plug without intermediate cables. The electrical pattern of the ignition coil is shown in the illustration.
The other components of the system do not differ from the before used Motronic M 1.7.
The steering box is equipped with a self diagnostic system and examines continuously the signals of the different sensors and compares it with the permitted limit values: If these values are exceeded, the system recognizes a disturbance and exchanges the abnormal values with average values accordingly, so that a trip up to the next base of the customer service net is ensured. This function is called „Limp home ".
In addition the self diagnostic system makes a fast and effective putting possible of the disturbances out under connection with Alfa Romeo the tester (see appropriate publications).
The system does not plan the examination by means of FLASHING CODES.
Fuel system circle
For the H'Ssö SJwird a closed tank vent system with Kohieaktivbehälter used (fuel steams arrive to the engine into the coal active container and over an electromagnetic valve are supplied).
1. Tank
2. Giver Kraftstoffstand
3. Giver Kraftstoffstand
4. Fuel separator
5. Connecting piece with tilting protection valve and 3-Wege-Lüftungsventil
6. Pump with giver Kraftstoffstand
7. Filter
8. Coal active container
9. Solenoid valve (steered from the steering box Motronic)
, 11
The tank was again designed due to the new rear axle and a larger capacity.
Due to the special form of the tank a special solution became concerning the arrangement of the pump and the fuel condition giver (3) developed. In the upper range of the tank is a giver with float.
When inserting the fuel condition giver (3 x) the installation direction must be considered „arrows ".
The pump is in one of the two lower ranges and leads the fuel over the filter to the injection nozzles. This concerns an electrical immersed pump, like with the previous versions. Together with the pump a further giver is present.
1. Pump
2. Giver
The moreover the return pipe of the engine is, in it is together with the third giver a device in the lower range, which passes the fuel on to the pump.
This concerns a device, which uses the suction effect due to the speed of the fuel return and so the necessary energy supplies, in order to promote the fuel from this part of the tank to the fuel pump.
1. Giver
2. Device fuel promotion
A: Return of the engine B: to the pump C: of the tank
Electrical pattern
j-9aj) Giver (under rear seat - left) Q-9tp giver (under rear seat - right) CL9cT) giver trunk
- M CZ&^iJwwne ** '
1B^E_______________________________________________ ON-BOARD BOARD
On-board board
Control light VISCOMATIC®
In the number of the control lights is also the announcement „VISCOMATIC ".
16                          15 14              13 12
The signal lamp shines when starting (approx. 2 seconds) and expires then; it remains illuminating against it if disturbances in the steering box arise VISCOMATIC. For further details, see section „VISCOMATIC ".
Indicate fuel and signal lamp to reserve
Also the activation of the fuel condition indicator and the signal lamp reserve is activated differently than so far.
Only one signal comes from the 3 givers (Televel) in the tank; this concerns 3 potentiometers, which are one behind the other switched and so an entirely proportional signal stood according to the fuel in the tank devoted.
This signal is administered by an appropriate unit („interfaces absorption and reserve "), which sends measures for the lighting of the signal lamp reserve, if the appropriate ohm value indicates a very low being located in the tank; in addition it sends the signal concerning the Kraftstoffstandes to the instrument.
This unit works with an internal delay of 15 seconds and „absorbs " so fast changes of the signals, which can occur in the curve or while driving downhill. For this reason the signal lamp not falsely lights up.
Ohm value depending upon announcements
Announcement on that
0 1/2
285 - r 315
123 + 139
46 + 54
Signal lamp
approximately 9 liters
On-board board: Interior pattern
Here only the specific part for the version is indicated