AUTOMOTIVE ELECTRICIANS PORTAL - FZCO

Alfa Romeo 156 2.4 JTD 20v da 04/98 a 02/99 — ABS — — Mechanical gearbox — WIRING DIAGRAM, LOCATION COMPONENTS, OPERATIONAL DESCRIPTION — WIRING DIAGRAM, LOCATION COMPONENTS, OPERATIONAL DESCRIPTION

Alfa Romeo 156 2.4 JTD 20v  da 04/98 a 02/99 — ABS —  — Mechanical gearbox — WIRING DIAGRAM, LOCATION COMPONENTS, OPERATIONAL DESCRIPTION — WIRING DIAGRAM, LOCATION COMPONENTS, OPERATIONAL DESCRIPTION
Wiring diagram

Components
Component codeNameAssembly reference
A1Battery-
A1Battery5530B
B1Junction unit5505A
B6MAXI FUSE box - 2-
B6MAXI FUSE box-2-
B11Controls lighting fuse-
B30ABS fuse and Air Bag-
B31ABS fuse-
B98Supplementary fuse box5505A
C1Battery earth-
C1Battery earth5530B
C10Front left earth5505A
C12ABS front earth5505A
D1Front / dashboard connection-
D1Front / dashboard coupling-
D5Front / ABS couping-
D5Front / ABS coupling-
E10Speedometer5560B
E30Check control5560C
H1Ignition switch5520A
I30Brake pedal switch5550D
K70.Left .front wheel sensor for ABS3340A
K70Front wheel sensor left for ABS3340A
K71.Right .front wheel sensor for ABS3340A
K71Front wheel sensor right for ABS3340A
K75Rear wheel sensor left for ABS3340A
K76Rear wheel sensor right for ABS3340A
K76Right rear wheel sensor for ABS3340A
M50ABS control unit3340A
R10Multiple tester connection-
Location of components

Components
Component codeNameAssembly reference
A1Battery-
A1Battery5530B
B1Junction unit5505A
B6MAXI FUSE box - 2-
B6MAXI FUSE box-2-
B11Controls lighting fuse-
B30ABS fuse and Air Bag-
B31ABS fuse-
B98Supplementary fuse box5505A
C1Battery earth-
C1Battery earth5530B
C10Front left earth5505A
C12ABS front earth5505A
D1Front / dashboard connection-
D1Front / dashboard coupling-
D5Front / ABS couping-
D5Front / ABS coupling-
E10Speedometer5560B
E30Check control5560C
H1Ignition switch5520A
I30Brake pedal switch5550D
K70.Left .front wheel sensor for ABS3340A
K70Front wheel sensor left for ABS3340A
K71.Right .front wheel sensor for ABS3340A
K71Front wheel sensor right for ABS3340A
K75Rear wheel sensor left for ABS3340A
K76Rear wheel sensor right for ABS3340A
K76Right rear wheel sensor for ABS3340A
M50ABS control unit3340A
R10Multiple tester connection-
DescriptionThe electronic anti-lock brake system (BOSCHABS) governs braking pressure sent to the wheels and prevents lossof grip under all tyre and road surface conditions.The system is designed to complement thenormal mechanical braking system and not to replace it. In thisway it ensures effective safety in the case of anomalies: the ABSuses the same fluid as the conventional mechanical braking system.Four sensors fitted to the four wheels informthe electronic control unit of wheel speed at every moment. In thisway, they detect wheel lock, wheel slip and loss of grip.Under these conditions, the control unitsends specific instructions to solenoids that modulate hydrauliccircuit pressure to eliminate lock and restore the car to withingrip limits. This ensures the shortest possible stopping distance,without losing control of the steering.Two adjustment solenoids (one for pressurecharging, the other for pressure discharging) are fitted for eachwheel.The sensors are active, i.e. they consistof a Hall-effect receiver that faces a magnetic coding device builtinto the hub bearing. Under these conditions, the signal is lessinfluenced by electromagnetic interference and temperature.The control unit also controls brake forcedistribution over the rear axle and thus replaces the mechanicalload proportioning valve used previously (EBD function: ElectronicBrake Distribution).The control unit is equipped with a self-diagnosticfunction: when an error occurs in the ABS system, a warning lightis turned on and the system is simultaneously deactivated. Underthese conditions, the car brakes using only the conventional system.When the control unit detects an error inthe EBD function, it simultaneously turns on the 'insufficient brakefluid level' and 'handbrake on' warning light as well as the ABSwarning light.Under these conditions, the rear brake distributioncontrol is also deactivated and the car must be driven with greatcare. For more details 3232922Characteristic of working principle3340A(B.S. ANTI-LOCK BRAKINGSYSTEM .) . The supply lines to the control unit andthe various system components (sensors and actuators) are protectedby a specific maxifuse and by a fuse in the additional fuse box.
Functional description ABS electronic control unit M50 issupplied (at pins 17 and 18) directly by the battery via a lineprotected by the ABS maxifuse, located directly on the battery A1 -connector C. The supply controlled by the ignition (15/54)reaches pin 15 from the line protected by fuse F6 of theadditional fuse box B98 A . The control unit is earthed via pins 19and 16. The four sensors K70 , K71 , K75 , K76 send wheel speed signals to pins 6-7, 4-5, 8-9 and 1-2of M50 respectively. Brake pedal switch I30 sends an enablementsignal to pin 14 of control unit M50 : the ABS cannot interveneunless the brake pedal is pressed. If the control unit M50 detects problemsrelating to the ABS function, it sends the instrument panel (check) E50 asignal, from pin 4, which lights up the 'ABS failure' warning light;if the problems concern the EBD function, the handbrake warninglight is lit up from pin 21. Pin 22 of M50 produces a speedometersignal (average speed of all four wheels) which is sent to the instrument panel E10 3234310SeeE4021SPEEDOMETER . The ABS includes an autodiagnostic system:when the control unit detects problems relating to the ABS functionit sends a signal from pin 20 to the check instrument E30 whichcontains the 'ABS failure' warning light. If the problems involvethe EBD function, the control unit also sends a signal from pin21 to instrument E30 to the 'insufficient brake fluid level'and 'handbrake applied' warning light. These signals cause the warning light tocome on because the instrument E30 supply is controlled bythe ignition (INT) from the line protected by fuse F4 of theadditional fuse box B98 B . The autodiagnostic data can be read by connectingto connector R10 : it receives signals from pin 11 of thecontrol unit M50 via the special diagnostic line. The ABS control unit M50 dialogueswith the engine management control unit M10 via the CAN line- pins 29 and 30, to indicate and irregularities in the ground,distinguished by the speed sensors installed on the individual wheels. Inthis way the engine management control unit can distinguish betweenthe variations in driving torque due to irregularities in the roadsurface and those due to misfire in the combustion chambers. The speedometer signal (vehicle speed) isalso sent to the M10 control unit via the CAN line.

Battery



A1A



A1B



A1C



A1C



A1C



A1C



A1D



A1D



A1D



A1D



A1



A1



A1



battery and leads



5530B10


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting21Place the car on a ramp.Undo the bolt securing the bracket on thebattery mount.Release the battery from the anchoragebracket complete with strap and remove.

5530B14


769768768

5530B18


Follow these precautions.769On batteries with an opticam hydrometer,electrolyte level and battery charge status can be monitored qualitativelyby examining the indicator colour:a light, bright colour indicates low electrolytelevel: top up with distilled water;a dark colour without a green area in thecentre indicates that the electrolyte level is correct but chargeis low: recharge the battery;a dark colour with a green area in themiddle indicates that both electrolyte level and charge status arecorrect: no action is necessary. For more details 3238420See subassembly5530 CURRENT GENERATOR . 768Proceed as follows.Check the battery voltage without loadusing the test device recommended by the Service outlets (e.g. 'MICRO360').Depending on the voltage values measured,which define the state of charge of the battery, proceed as follows: If the voltage without load is less than12.10 V, replace the battery ( 32384295530B10battery - r+r ). If the voltage without load is over 12.10V but less than 12.50 V, recharge the battery ( 32384305530B14battery - recharge ). If the voltage without load is over 12.50V, the battery is efficient.If necessary, top up the electrolyte asfollows.Carefully remove the cap strip.Top up with distilled and deionized water,taking care not to allow electrolyte to splash out.768

5530B22


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting21Place the car on the liftingbridge.1. Open engine compartment cap and disconnect battery negative terminal.2. Disconnect mass terminal on side member.3. Lift the car and disconnect mass terminal on gearbox.4. Lower the car again and remove battery earth lead.2018767

5030B26



5030B40


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting21Disconnect the battery negative terminal.1. Open the protective cover2. Loosen the nut and disconnect the ABS supply lead3. Loosen the nut and disconnect the starter motor supply lead4. Undo the clip and undo the box retaining bolts.5. Loosen the battery positive terminal nut.2018769

5530B52


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting213238429-5530B10battery - r+rRelease the air duct hose from the mountingbracket on the drip tray. Remove the relay shield.1. Release the relays from the battery drip tray and remove them.2. Undo the nut fixing the air filter mounting bracket to the batterydrip tray.3. Undo the two fixing nuts (3a) and move the connections/electricalwiring mounting bracket (3b) aside.4. Release the accelerator cable from the fastening on the bracket.2018771

Junction unit



B1A



B1A



B1B



B1B



B1B



B1C



B1C



B1C



B1C



B1C



B1C



B1C



B1C



B1C



B1C



B1C



B1D



B1D



B1D



B1D



B1D



B1D



B1D



B1D



B1D



B1D



B1D



B1D



B1D



B1D



B1D



B1E



B1E



B1E



B1F



B1F



B1G



B1G



B1G



B1G



B1H



B1H



B1I



B1I



B1I



B1I



B1I



B1I



B1I



B1J



B1J



B1J



B1J



B1J



multi-function components



5505A10


769

5505A16


769

5505A18


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting213238830-7040G24switch for facia compartmentlight - r+r3238829-7040G20facia compartment light bulb holder - r+r3238795-7040A31flap assembly - r r1. Undo the bolts.2. Move the integrated service control unit slightly.3. Disconnect the electrical connections (3a, 3b, 3c).2018617

5505A30


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting21Remove components obstractingaccess to earth carrier node.1. Unscrew screw.2. Disjoin earth carrier node.2018618

5505A38



MAXI FUSE box - 2



B6A



B6A



B6A



B6B



Controls lighting fuse



B11



B11



ABS fuse and Air Bag



B30



ABS fuse



B31



Supplementary fuse box



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98A



B98B



B98B



B98B



B98B



B98B



B98C



B98C



B98C



Front left earth



C10A



C10A



C10A



C10A



C10A



C10A



C10A



C10A



C10A



C10B



C10B



C10B



C10B



C10C



Front / dashboard connection



D1B



D1B



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



D1



Front / ABS couping



D5A



D5A



D5A



D5A



D5A



D5B



D5B



D5B



D5B



D5B



D5B



D5B



D5B



D5B



D5B



D5B



D5B



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



D5



Power supply and earths



E1010



E1020



E1020



E1020



E1010



E1010



E1010



E1010



E1010



E1010



E1010



E1010



E1010



E1010



E1010



E1010



E1010



analogue control panel



5560b02


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting211. Unscrew the screw.2. Remove the frame (2a) and take it off the check clamps (2b).3. Unscrew the screws.4. Remove the speedometer/odometer (4a) from from support and moveit.5. Disconnect the electric connections (5a, 5b).2018847

5560B03


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting211. Unscrew the screw.2. Remove the frame (2a) and take it off the check clamps (2b).3. Unscrew the screws.4. Extract the speedometer (4a) from the support (4b) e move it.5. Disconnect the electric connections (5a, 5b).2018848

5560B06


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting21For the replacement of lampsof the speedometer/odometer proceed as follows.3238496-5560B02kilometre/mileometer - r r1. Turn and remove the lamp holder of the instrument lamp (1a) orthe lamp holder of the display lamp (1b).2. Remove the lamp from lamp holder. Pressure joint.2018849

5560B12



other instruments



5560C51


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting213238343-5040D22control (one) of airconditioner control support - arrange3238986-7065C42ashtray (one) r+r3238514-5570T80car radio unit - r+r3237934-2125C24gear lever knob - r + r3238802-7040A60under facia trim - r+r1. Unscrew the bolts2. Move the analogue instrument panel.3. Disconnect the electrical connection and keep the instrument.2018851

5560C60


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting211. Remove the component with theIU+2019 special tool .2. Disconnect the electric connection and remove the component.2018855

5560C64



Ignition switch



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1A



H1B



H1B



H1B



H1B



H1B



H1B



ignition switch



5520A12


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting213238121-4110A11steering wheel - r+rfor replacement or check for versions with air bag3238793-7040A26steering column trim - r+r3238476-5550A12complete stalk unit - r+r for versions with air bag1. Disconnect electric connection from ignition switch.2. Unscrew screws (2a) and remove starter switch (2b). 2018661

5520A14


769

5520A16


769

5520A18


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting21Unloose fixing screws and removesteering column guide.1. Detach down-lead cable.2018668

brake and reversing lights



5550D10


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting211. Disconnect the electrical connection.2. Turn IU+2019 switch (2a) anticlockwisely of about 60° and extractit.To make the opening easier operate by a wrench on the exagonalsection (2b) of the IU+2019 switch. 2018839

5550D14



5550D16


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting211. Open the boot lid, turn and undo the lower studs securing theupper trim.2. Lower upper trim (2a) and unscrew knob (2b) securing the thirdbrake light.3. Prise out the brake light and remove.4. Prise electrical connection (4a) out of support (4b) and disconnect.Recover the light cluster.2018841

5550D17


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting213238489-5550D16third stop light - r+r1. Unscrew the bolts and remove the mount from the light.2. Undo the bolts.3. Remove the bulb holder.4. Remove the bulbs (press-fit type)2018843

5550D18


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting213238117-3380A44handbrake/linkage protection- r+r1. Unscrew the screw.2. Move IU+2019switch.3. Disconnect the electrical connection and recover IU+2019switch.2018844

5550D22


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting21Place the car on an auto lift.1. Lift the car and disconnect the electrical connection of thereserving light switch.2. Unscrew and take the reserve light switch off.2018845

5550D26



.Left .front wheel sensor for ABS



K70



K70



K70



K70



K70



abs check/adjustment devices



3340A12


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting213238429-5530B10battery - r+r1. Drain the brake-clutch fluid from the reservoir using a suitablesyringe.2. Disconnect the air inlet pipe from the inlet manifold.2017884

3340A13


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting213238091-3340A12A'B.S. system. - electronicand hydraulic CONTROL UNIT R.R.3238429-5530B10battery - r+r3238435-5530B52Battery DRIP TRAY/SUPPORT - R.R.Disconnect the various pipes from the bandson the A.B.S. control unit mounting.1. Undo the bolts (1a) and remove the A.B.S. control unit mounting(1b).2017897

3340A20


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting21 Proceed with the removal 3238429-5530B10battery - r+r . Proceed with the removal 3238091-3340A12A'B.S. system. - electronicand hydraulic CONTROL UNIT R.R. . 1. At the bench, undo the bolts (1a) and separate ABS electroniccontrol unt (1b) from the hydraulic assembly. 2017898

3340A30


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting21Disconnect the battery negative(-) terminal. 1. Disconnect the electrical connection for one of the front wheelrpm sensors.2. Undo the bolt (2a) and remove one of the the front wheel rpmsensors (2b) complete with electrical wiring.2017900

3340A32



3340A34


<anchor>0</anchor><span>Removing</span><icon><imageid>20</imageid></icon>1Refitting21Disconnect the battery negative(-) terminal. 1. Disconnect the electrical connection for one of the rear wheelrpm sensors.2. Undo the bolt (2a) and remove the rpm sensor for one of the rearwheels (2b) complete with electrical wiring.2017901

3340A44



3340A48



.Right .front wheel sensor for ABS



K71



K71



K71



K71



K71



Rear wheel sensor left for ABS



K75



K75



K75



K75



K75



Rear wheel sensor right for ABS



K76



K76



K76



K76



K76



Multiple tester connection



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10



R10