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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
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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
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38C-72
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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
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38C-73
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V2
ANTI-LOCK BRAKING SYSTEM
Diagnostic - Fault finding chart38C
ALP 5Unexpected ABS operation at low speed and with slight
pedal pressure
NOTESOnly consult this customer complaint after a complete check with the diagnostic tool.
Important: ABS regulation may be unresponsive when the vehicle is driven on surfaces
such as icy roads, cobbled streets, etc.
It is possible to feel brake pedal vibrations which are associated with the reaction of the system in particular
circumstances, such as:
–crossing rumble strips,
–tight cornering with lifting of the inside rear wheel.
These vibrations may be linked to simple brake limiter activation, when the pressure on the rear axle is limited.
If the fault is different, check the speed sensor connectors (micro-breaks) as well as the air gaps.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ESPBOSCH_V08_ALP05 /ESPBOSCH_V09_ALP05/ESPBOSCH_V0A_ALP05/
ESPBOSCH_V0B_ALP05 /ESPBOSCH_V11_ALP05/ESPBOSCH_V12_ALP05BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12
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38C-81
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V2
ANTI-LOCK BRAKING SYSTEM
Diagnostic - Fault finding chart38C
ALP 13 Faulty brake lights lighting
NOTESOnly consult this customer complaint after a complete check with the diagnostic tool.
Using the diagnostic tool, check that ET017 is functioning correctly.
If not, apply the fault finding procedure described above for ET017.
If the lights still do not work, check the functioning of the light-switch relay.
The relay is passed at rest (check the continuity between tracks 3 and 4 of the relay). Replace the relay if
necessary.
Check the continuity of the connection between track 1 of the brake light switch and track 4 of the relay mounting.
Repair if necessary.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ESPBOSCH_V08_ALP13 /ESPBOSCH_V09_ALP13/ESPBOSCH_V0A_ALP13/
ESPBOSCH_V0B_ALP13 /ESPBOSCH_V11_ALP13/ESPBOSCH_V12_ALP13BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12
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38C-83
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V2
ANTI-LOCK BRAKING SYSTEM
Diagnostic - Fault finding chart38C
*ASR: Traction control
ALP15ESP warning light comes on with the "ASR* disconnected or off"
message when the current is switched on without pressing the
ESP disconnection button
NOTESConsult this customer complaint only if the "Service", "ABS" and "Brake" warning lights
are not lit.
After disconnecting the battery, it is probable that the electric power steering loses the steering wheel angle
sensor indexing (the electric power steering no longer sends the steering wheel angle signal to the ESP, which is
then disabled).
The ESP system is not faulty, no fault is present in the fault memory, the ESP warning light comes on and the
"ASR disconnected or off" message indicate this transient and reversible status.
To restore the electric power steering indexing and enable the ESP again, it is necessary to:
–switch on the ignition or start the engine (to obtain maximum steering assistance),
–turn the steering wheel slowly to full right lock, to full left lock, then return slowly to the centre point after going
slightly past it,
–the ESP warning light should go out and the message "ASR disconnected or off" should disappear,
–stop the engine and switch off the ignition,
–switch on the ignition, start the engine and see that the warning light no longer lights up.
If the warning light and the message reappear, start the procedure described above again.
If the operation fails again or if this customer complaint appears without the battery having been disconnected, run
fault finding on the electric power steering and repair accordingly.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ESPBOSCH_V08_ALP15 /ESPBOSCH_V09_ALP15/ESPBOSCH_V0A_ALP15/
ESPBOSCH_V0B_ALP15 /ESPBOSCH_V11_ALP15/ESPBOSCH_V12_ALP15BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12
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38C-84
MR-372-J84-38C050$930_eng.mif
V2
38C
ANTI-LOCK BRAKING SYSTEM
Diagnostic - Fault finding chart
ALP 16Intermittent illumination of brake, ESP, ABS, SERVICE and STOP
warning lights and the message "brake failure" on the instrument
panel with no fault codes in the computer
NOTESOnly consult this customer complaint after a complete check with the diagnostic
tool.
Check the condition and connection of the
battery terminals.
Is the battery in good condition?
YES
Check the 50A power fuse in position 5 on
the power fuse board. Check fuse F13 (25A)
on the UPC and the correct locking of the
grey 4-track PPH1 connector (Vdiag 44) or
the 25A fuse F8 on the UPC and the correct
locking of the black 6-track CM connector
(Vdiag 48 or higher).
Are the fuses and connectors correct?
YES
Check the connection and condition of the tab
1 red wire of the grey connector.
Is the connector correct?
YES
NOClean the battery terminals.
NOIf the connector is faulty and there is a repair
procedure (see Technical Note 6015A,
Electrical wiring repair, Wiring: Precautions
for repair), repair the connector, otherwise
replace the wiring.
Replace any faulty fuses. Switch on the ignition
again.
Is the replaced fuse or fuses correct?
NO
Check the insulation to earth between:
–fuse 50A and track 2 of the computer
–fuse 25A and track 3 of the computer
Are the connections correct?
NO YES
Contact the Techline.
If the connection(s) are faulty and there is a repair method
(see Technical Note 6015A, Repairing electrical wiring,
Wiring: Precautions for repair), repair the wiring, otherwise
replace it.
NO
If the connector is faulty and there is a repair method (see Technical
Note 6015A, Repairing electrical wiring, Wiring: Precautions for repair),
repair the connector, otherwise replace the wiring.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ESPBOSCH_V08_ALP16 /ESPBOSCH_V09_ALP16/ESPBOSCH_V0A_ALP16/
ESPBOSCH_V0B_ALP16 /ESPBOSCH_V11_ALP16/ESPBOSCH_V12_ALP16BOSCH 8.0 ESP
Vdiag No.: 08, 09, 0A,
0B, 11, 12