Page 65 of 85
ANTI-LOCK BRAKING SYSTEM
BOSCH 8.0 ESP Vdiag No.: 08, 09, 0A, 0B, 11, 1238C
38C - 65V2 MR-372-J84-38C050$806_eng.mif
BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12
ET017
CONTINUED
Pressed STATUS, Brake pedal released.
Check the condition and fitting of the brake light switch, the brake lights fuse and the conformity of the bulbs.
Remove the brake light switch and check that it is operating correctly:
Continuity between tracks Insulation between tracks
Switch pressed
(Brake pedal released)3 and 4 1 and 2
Switch released
(Brake pedal depressed)1 and 2 3 and 4
Replace the switch if necessary.
Check and if necessary repair the insulation from 12 V on the connection between track 1 of the brake light switch
connector and track 30 of the computer connector.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
Page 66 of 85

ANTI-LOCK BRAKING SYSTEM
BOSCH 8.0 ESP Vdiag No.: 08, 09, 0A, 0B, 11, 1238C
38C - 66V2 MR-372-J84-38C050$806_eng.mif
BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12
ET023
ESP ON/OFF BUTTON
NOTESSpecial notes:
Carry out the checks only if the "pressed" and "released" statuses are not consistent
with the button position.
STATUS: "Depressed"
Ensure that the ESP start/stop button connector is in good condition and correctly connected. Repair if necessary.
Check there is no continuity between switch tracks A2 and B1 in the released position. If there is continuity,
replace the switch.
Check the continuity and insulation against the earth of the connection between:
Switch connector track B1 Track 31 computer connector
STATUS: "Released"
Ensure that the ESP start/stop button connector is in good condition and correctly connected. Repair if necessary.
Check the continuity between button tracks A2 and B1 in the pressed position. If there is no continuity, replace
the switch.
Check for earth on Track A2 of the button connector.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ESPBOSCH_V08_ET023/ESPBOSCH_V09_ET023 /ESPBOSCH_V0A_ET023/
ESPBOSCH_V0B_ET023/ESPBOSCH_V11_ET023/ESPBOSCH_V12_ET023
Page 67 of 85
ANTI-LOCK BRAKING SYSTEM
BOSCH 8.0 ESP Vdiag No.: 08, 09, 0A, 0B, 11, 1238C
38C - 67V2 MR-372-J84-38C050$868_eng.mif
BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12ANTI-LOCK BRAKING SYSTEM
NOTESOnly consult this customer complaint after a complete check with the diagnostic tool.
FAULTS DETECTED ON BRAKING WITH ABS/BRAKING REGULATION
LOCKING OF ONE OR MORE WHEELS ALP2
PULLINGALP3
DRIFTALP4
UNEXPECTED ABS OPERATION AT LOW SPEEDS AND SLIGHT PEDAL
PRESSUREALP5
UNEXPECTED ABS OPERATION ON A POOR ROAD SURFACE ALP6
UNEXPECTED ABS OPERATION WHEN USING SPECIAL EQUIPMENT
(RADIO TELEPHONE, CB, etc.)ALP7
LENGTHENING OF BRAKE PEDAL TRAVEL FOLLOWING ABS
(WITH PEDAL RECEDING WHEN ENTERING ABS)ALP8
SPONGY PEDAL ALP9
BRAKE PEDAL VIBRATION ALP10
NOISES FROM THE PUMP, PIPES OR HYDRAULIC UNIT ALP11
MR-372-J84-38C050$868_eng.mif
Page 68 of 85
ANTI-LOCK BRAKING SYSTEM
BOSCH 8.0 ESP Vdiag No.: 08, 09, 0A, 0B, 11, 1238C
38C - 68V2 MR-372-J84-38C050$868_eng.mif
BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12
NOTESOnly consult this customer complaint after a complete check with the diagnostic tool.
OTHER CASES
NO DIALOGUE WITH THE ABS COMPUTER ALP1
"ABS COMPUTER NOT DETECTED" DURING MULTIPLEX NETWORK TEST
ON CLIPALP12
FAULTY BRAKE LIGHTS ALP13
ERRATIC TRIGGERING OF ESP ALP14
ESP WARNING LIGHT COMES ON WITH THE "ASR DISCONNECTED"
MESSAGE WHEN THE CURRENT IS SWITCHED ON WITHOUT PRESSING THE
ESP DISCONNECTION BUTTONALP15
INTERMITTENT ILLUMINATION OF BRAKE, ABS, SERVICE AND STOP
WARNING LIGHTS AND THE MESSAGE "BRAKE FAILURE" ON THE
INSTRUMENT PANEL WITH NO FAULT CODES IN THE COMPUTERALP16
Page 69 of 85

38C-69
MR-372-J84-38C050$930_eng.mif
V2
38C
ANTI-LOCK BRAKING SYSTEM
Diagnostic - Fault finding chart
ALP 1 No dialogue with the ABS computer
NOTESSpecial note:
To run fault finding on the vehicle's computers, switch on the ignition in fault finding
mode (forced + after ignition feed), i.e. proceed as follows:
–With the vehicle card in the card reader, press the Start button for more than
5 seconds without starting conditions being met.
Check that the CLIP diagnostic tool is equipped with the latest update available.
Try to establish dialogue with a computer on another vehicle to make sure that the diagnostic tool is not faulty.
If the tool is not at fault, and dialogue cannot be established with any other computer on the same vehicle, the
cause could be a faulty computer interfering on the multiplex network. Check the battery voltage and carry out the
operations necessary to obtain the correct voltage (9.5 V < battery voltage < 17.5 V).
Carry out a fault finding procedure on the multiplex network using the diagnostic tool.
Check the presence and the condition of the ABS fuses on the passenger compartment fuse board and in the
engine fuse box.
Check that the computer connector is properly connected and check the condition of its connections.
Check the ABS earths (good condition, not corroded, earth screw on top of the ABS unit tight).
Check that the supply to the computer is correct:
–Earth on tracks 1 and 4 of the 46-track connector.
–+ before ignition feed on tracks 2 and 3 of the 46-track connector.
–+ after ignition feed on track 18 of the 46-track connector.
Check that the power supply to the diagnostic socket is correct:
–+ before ignition feed on track 16.
–+ after ignition feed on track 1.
–Earth on tracks 4 and 5.
If dialogue has still not been established after these checks, contact the Techline.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ESPBOSCH_V08_ALP01 /ESPBOSCH_V09_ALP01/ESPBOSCH_V0A_ALP01/
ESPBOSCH_V0B_ALP01 /ESPBOSCH_V11_ALP01/ESPBOSCH_V12_ALP01BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12
MR-372-J84-38C050$930_eng.mif
Page 70 of 85

38C-70
MR-372-J84-38C050$930_eng.mif
V2
ANTI-LOCK BRAKING SYSTEM
Diagnostic - Fault finding chart38C
ALP 2 Locking of one or more wheels
NOTESOnly consult this customer complaint after a complete check with the diagnostic tool.
Reminder: wheel lock on a vehicle equipped with ABS, or tyre squealing perceived by the customer as locking,
may be part of the normal operation of the system and should not be automatically considered as faults:
–Braking with ABS on very poor roads (significant squealing).
However, if the wheels are actually locking, raise the vehicle in order to be able to turn the wheels and check:
–Possible inversion when connecting the speed sensors.
Using parameters PR001, PR002, PR003 and PR004, rotate the wheels slowly and check the consistency of the
results obtained.
If the value measured is zero, rotate the other wheels to confirm an electrical inversion of the sensors and repair
the wiring harness.
–Possible inversion of pipes on the hydraulic unit.
Use commands AC003 Front left-hand wheel solenoid valves, AC004 Front right-hand wheel solenoid
valves, AC005 Rear left-hand wheel solenoid valves and AC006 Rear right-hand wheel solenoid valves
while depressing the brake pedal and check for the occurrence of 5 locking/unlocking cycles on the wheel
concerned (see Dealing with commands). If the 5 cycles do not occur on the wheel tested (wheel remains
locked), check whether they occur on another wheel to confirm transposed pipes.
If the 5 cycles are not detected on a wheel and the pipes have not been subject to inversion, replace the hydraulic
unit.
Check that the sensor casing is secured when rotating.
Check the quality of the mounting of the wheel speed sensor (correct clipping without excessive play).
Check the conformity of the targets using special command SC001 "Check target teeth": condition, number of
teeth = 48.
If the fault is still present after these checks, contact the Techline.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ESPBOSCH_V08_ALP02 /ESPBOSCH_V09_ALP02/ESPBOSCH_V0A_ALP02/
ESPBOSCH_V0B_ALP02 /ESPBOSCH_V11_ALP02/ESPBOSCH_V12_ALP02BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12
Page 71 of 85

38C-71
MR-372-J84-38C050$930_eng.mif
V2
ANTI-LOCK BRAKING SYSTEM
Diagnostic - Fault finding chart38C
ALP 3 Pull
NOTESOnly consult this customer complaint after a complete check with the diagnostic tool.
Disconnect one wheel speed sensor. Start the
engine and check that only the ABS fault warning
light comes on. Do not drive the vehicle if the brake
fault warning light is also lit, as the brake limiter
function is no longer guaranteed to operate
correctly. Carry out a road test with the ABS
deactivated.
Is the fault still present under these conditions?
no
Raise the vehicle so that you can rotate the wheels
and check:
–Possible inversion when connecting the speed
sensors.
–Possible inversion of pipes on the hydraulic unit.
To carry out these two tests, refer to and follow the
procedures given in ALP 2.
Check the condition of the ABS targets and that they
conform to specifications.
Also check the sensor/target air gap over one
revolution of each front and rear wheel.
If the fault is still present, contact the Techline.
yesIf the brake pedal travel is relatively long,
bleed the brake circuit.
If the travel is normal, check the tyre
pressures, the front axle, or for any leaks
in the circuit.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ESPBOSCH_V08_ALP03 /ESPBOSCH_V09_ALP03/ESPBOSCH_V0A_ALP03/
ESPBOSCH_V0B_ALP03 /ESPBOSCH_V11_ALP03/ESPBOSCH_V12_ALP03BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12
Page 72 of 85

38C-72
MR-372-J84-38C050$930_eng.mif
V2
ANTI-LOCK BRAKING SYSTEM
Diagnostic - Fault finding chart38C
ALP 4 Drift
NOTESOnly consult this customer complaint after a complete check with the diagnostic tool.
Disconnect one wheel speed sensor. Start the
engine and check that only the ABS fault warning
light comes on. Do not drive the vehicle if the brake
fault warning light is also lit, as the brake limiter
function is no longer guaranteed to operate
correctly. Carry out a road test with the ABS
deactivated.
Is the fault still present under these conditions?
no
Normal behaviour linked to the system operation
during the regulation phase, mainly on surfaces with
uneven grip or which are poorly laid.
yesRoad handling fault not connected with
the ABS.
Check the condition of the brake linings
and that they are to specification and
check the tyre pressures, the front axle,
etc.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ESPBOSCH_V08_ALP04 /ESPBOSCH_V09_ALP04/ESPBOSCH_V0A_ALP04/
ESPBOSCH_V0B_ALP04 /ESPBOSCH_V11_ALP04/ESPBOSCH_V12_ALP04
BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12