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38C-39
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V1
ANTI-LOCK BRAKING SYSTEM
Fault finding - Interpretation of faults
MK70 ABS
Vdiag No: 04
38C
DF098
PRESENT
OR
STOREDNO UCH MULTIPLEX SIGNAL
NOTESSpecial notes:
Even though it is stored in the computer, this fault does not cause the warning lights to
come on or a fault message, because the ABS system is not faulty.
Perform fault finding on the UCH (Passenger compartment connection unit) using the
diagnostic tool.
Note:
After repairing the fault in the UCH (Passenger compartment connection unit),
clear the fault memory in the ABS system.
Priority in the event of a number of faults:
Deal with fault DF152 Multiplex network
first if it is present or stored.
Conditions for applying the fault finding procedure to stored faults:
The fault is declared present when the engine is started up.
Check the UCH (Passenger compartment connection unit) using the diagnostic tool.
Run a multiplex network test (see 88B, Multiplex).
If the fault is still present, contact the Techline.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ABS_V04_DF098
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38C-43
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V1
ANTI-LOCK BRAKING SYSTEM
Fault finding - Interpretation of faults
MK70 ABS
Vdiag No: 04
38C
DF188
PRESENT
OR
STOREDBRAKE LIGHT SWITCH CIRCUIT
1.DEF: Inconsistency
NOTESConditions for applying the fault finding procedure to stored faults:
Clear the stored fault, carry out a road test at a speed of > 36 mph (60 km/h) and test
the brakes using ABS. Use the interpretation of the fault if it recurs.
Special notes:
The fault is detected if the computer does not detect a brake lights switch status
change for 4 acceleration/braking cycles and/or the contact is closed for over
6 minutes with the vehicle speed above 24 mph (40 km/h).
Using the diagnostic tool, check on the statuses screen that ET017 Brake pedal recognises the depressed and
released positions of the brake pedal.
If the pedal position is not detected, use the interpretation of ET017.
If the fault is still present, contact the Techline.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ABS_V04_DF188
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38C-50
MR-413-X44-38C000$517_eng.mif
V1
ANTI-LOCK BRAKING SYSTEM
Fault finding - Interpretation of faults
MK70 ABS
Vdiag No: 04
38C
DF311
PRESENT
OR
STOREDNO BVR MULTIPLEX SIGNAL
NOTESSpecial notes:
Even though it is stored in the computer, this fault does not cause the warning lights to
come on or a fault message, because the ABS system is not faulty.
Perform fault finding on the BVR (sequential gearbox) using the diagnostic tool.
Note:
After repairing the fault in the BVR (sequential gearbox), clear the fault memory
in the ABS system.
Priority in the event of a number of faults:
Deal with fault DF152 Multiplex network first if it is present or stored.
Conditions for applying the fault finding procedure to stored faults:
The fault is declared present when the engine is started up.
Check the gearbox type configuration with the diagnostic tool, using command LC008 Gearbox type.
If the configuration is not correct, configure the gearbox type present on the vehicle using configuration command
CF079 Gearbox type.
Check the BVR (sequential gearbox) using the diagnostic tool.
Run a multiplex network test (see 88B, Multiplex).
If the fault is still present, contact the Techline.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ABS_V04_DF311
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38C-53
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V1
38C
ANTI-LOCK BRAKING SYSTEM
Fault finding - Interpretation of statuses
ET017
BRAKE PEDAL
NOTESSpecial notes:
Only carry out the checks if the PRESSED and RELEASED statuses are inconsistent
with the pedal position.
Use the Technical Note wiring diagram for New Twingo.
STATUS
"RELEASED"
Brake pedal
depressed
If brake lights operate:
–Check the continuity of connection 65A between components 160 and 1094.
If the connector is faulty (see NT6015, Repairing electrical wiring, wiring: Precaution
for repairs), repair the connector, otherwise replace the wiring.
If the brake lights are not working:
–Check the condition, mounting and adjustment of the brake light switch and the
conformity of the bulbs.
–Remove the brake light switch and check that it is operating correctly:
Connection continuity Connection insulation
Switch pressed
(Brake pedal released)AP10 and 5A AP10 and 65A
Switch released
(Brake pedal depressed)AP10 and 65A AP10 and 5A
–Replace the switch if necessary.
Intermediate connector R107 and component 160 and 1081 disconnected:
–Check the continuity and insulation of connection AP10 between
component 1016 and intermediate connector R107.
–Check the continuity and insulation of connection AP10 between
component 160 and intermediate connector R107.
If the connector is faulty (see NT6015, Repairing electrical wiring, wiring:
Precaution for repairs), repair the connector or the wiring, otherwise replace the
wiring.
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ABS_V04_ET017
MK70 ABS
Vdiag No: 04
MR-413-X44-38C000$658_eng.mif
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V1
MK70 ABS
Vdiag No: 04ANTI-LOCK BRAKING SYSTEM
Fault finding - Interpretation of statuses38C
ET017
CONTINUED 1
Connectors of components 645, 172, 173, 639 and 1094, intermediate connectors
R107 and R15 and connector of component 119 (if present on the vehicle)
disconnected from connection 65A:
–Check the insulation of connection 65A between component 160 and
intermediate connector R107.
–Check the insulation of connection 65A between component 172 and
intermediate connector R107.
–Check the insulation of connection 65A between component 173 and
intermediate connector R107.
–Check the insulation of connection 65A between intermediate connectors R107
and R15.
–Check the insulation of connection 65A between component 639 and
intermediate connector R15.
–Check the insulation of connection 65A between component 645 and
intermediate connector R107.
If the connector is faulty (see NT6015, Repairing electrical wiring, wiring:
Precaution for repairs), repair the connector, otherwise replace the wiring.
–Check for + 12 V after ignition feed on connection AP10 of component 1016 to
earth MAH.
If the checks reveal no faults, carry out a check of each component associated with
connection 65A and AP10 (short circuits).
Check the condition and positioning of the F5 5A fuse (see MR411 Mechanical
systems, 81C, Fuses: 16A).
–Check the condition, mounting and adjustment of the brake light switch and the
conformity of the bulbs.
–Remove the brake light switch and check that it is operating correctly:
Connection continuity Connection insulation
Switch pressed
(Brake pedal released)AP10 and 5A AP10 and 65A
Switch released
(Brake pedal
depressed)AP10 and 65A AP10 and 5A
–Replace the switch if necessary.
Connectors of components 645, 172, 173, 639 and 1094, intermediate
connectors R107 and R15 and connector of component 119 (if present on the vehicle)
disconnected from connection 65A
–Check the insulation of connection 65A between component 160 and
intermediate connector R107.
STATUS
DEPRESSED:
Brake pedal
released
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
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38C
ANTI-LOCK BRAKING SYSTEM
Fault finding - Command summary table
Tool command Diagnostic tool title
AC003Front left-hand wheel solenoid valves
AC004Front right-hand wheel solenoid valves
AC005Rear left-hand wheel solenoid valves
AC006Rear right-hand wheel solenoid valves
AC016Pump motor test
AC153Bleed front left-hand wheel
AC154Bleed front right-hand wheel
AC155Bleed rear left-hand wheel
AC156Bleed rear right-hand wheel
AC195Vehicle speed signal
AC196Hazard warning light activation request
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
MK70 ABS
Vdiag No: 04
MR-413-X44-38C000$799_eng.mif
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38C-63
MR-413-X44-38C000$846_eng.mif
V1
ANTI-LOCK BRAKING SYSTEM
Fault finding - Dealing with command modes
MK70 ABS
Vdiag No: 04
38C
AC196
HAZARD WARNING LIGHT ACTIVATION REQUEST
NOTESConditions of use of the command.
Ignition on, engine stopped and vehicle speed zero.
Before using the command, check that the battery is fully charged.
This command sends a hazard warning light activation request to the UCH (Passenger compartment connection
unit) to test their operation in the event of emergency braking (depending on UCH, Passenger Compartment
Connection Unit configuration).
AFTER REPAIRClear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
ABS_V04_AC196
Page 64 of 76
38C-64
MR-413-X44-38C000$893_eng.mif
V1
38C
ANTI-LOCK BRAKING SYSTEM
Fault finding - Customer complaints
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 ALP 2
PULLING ALP 3
DRIFT ALP 4
UNEXPECTED ABS OPERATION AT LOW SPEEDS AND SLIGHT PEDAL
PRESSURE ALP 5
UNEXPECTED ABS OPERATION ON A POOR ROAD SURFACE ALP 6
UNEXPECTED ABS OPERATION WHEN SPECIAL EQUIPMENT
USED (CAR PHONE, CB, ETC.) ALP 7
EXTENSION OF BRAKE PEDAL TRAVEL FOLLOWING
REGULATION PHASE (WITH LEAKING PEDAL WHEN STARTING
REGULATION PHASE)ALP 8
SPONGY PEDAL ALP 9
BRAKE PEDAL VIBRATION ALP 10
NOISES FROM THE PUMP, PIPES OR HYDRAULIC UNIT ALP 11
OTHER CASES
NO DIALOGUE WITH THE ABS COMPUTER ALP 1
MK70 ABS
Vdiag No: 04
MR-413-X44-38C000$893_eng.mif