
AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Fault Interpretation
88C - 59
88C
V3 MR-372-J84-88C000$072.mif
AIRBAG ACU4
Vdiag: 04
DF232
PRESENT
DRIVER'S SEAT BELT BUCKLE SENSOR CIRCUIT
CO : Open circuit
CC.0 : Short circuit to earth
CC.1 : Short circuit to + 12 V
1.DEF : Configuration
2.DEF : Below minimum threshold
3.DEF : Values out of range
NOTESIf 1.DEF Check and adjust the computer configuration.
Special notes: never carry out measuring operations on trigger lines using any tool
other than CLIP or XRBAG.
Use the 64-track (Elé. 1717) adapter for working on the computer connector and the
22-track (Elé. 1687) adapter for working on the seat.
CO - CC.0 - CC.1 -
2.DEF - 3.DEF
NOTESSpecial notes: None.
Check the condition and connections of the 64-track computer connector (lock system, wiring etc.).
Make sure the driver's seat belt buckle sensor is properly connected and test its connections.
Ensure continuity and insulation of the connections between:
Terminal block Elé. 1717 terminal 11 Track 2 buckle sensor connector.
Terminal block Elé. 1717 terminal 12 Track 1 buckle sensor connector
If the connection is OK, replace the driver's seat belt buckle sensor.
If the connection is faulty:
Check the connections of the 22-track connector under the seat, seat side (tracks 5 and 6). Repair if
necessary. Attach the 22-track (Elé. 1687) test adapter under the seat (point C1).
Ensure continuity and insulation of the connections between:
Terminal block Elé. 1687 terminal 5 Track 2 buckle sensor connector.
Terminal block Elé. 1687 terminal 6 Track 1 buckle sensor connector
Repair if necessary.
Check the connections of the 22-track connector under the seat, computer side (tracks 5 and 6).
Repair if necessary. Attach the 64-track (Elé. 1717) test adapter to the computer (point C0).
Ensure continuity and insulation of the connections between:
Terminal block Elé. 1717 terminal 11 Track 5 22-track connector
Terminal block Elé. 1717 terminal 12 Track 6 22-track connector
If the connection is faulty, repair or replace the harness.
AFTER REPAIRClear the computer memory then switch off the ignition.
Check again using the diagnostic tool.
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Fault Interpretation
88C - 60
88C
V3 MR-372-J84-88C000$072.mif
AIRBAG ACU4
Vdiag: 04
DF239
PRESENT
REAR SEAT BELT RETRACTORS CIRCUIT
CC : Short circuit
CO : Open circuit
CC.1 : Short circuit to + 12 V
CC.0 : Short circuit to earth
1.DEF : Configuration
NOTESIf 1.DEF, check and adjust the computer configuration.
Special notes: the rear seat belt retractors are serially wired.
Never do measuring on the trigger lines with any tool other than CLIP or XRBAG.
Use the 64-track (Elé. 1717) adapter to work on the computer connector.
CO - CC
NOTESSpecial notes: Correct the trigger line configuration if the
vehicle is not fitted with rear seat-belt retractors.
Lock the computer.
Switch off the ignition and check that the ignition module of the rear seat belt retractor, driver's side is correctly
connected.
Disconnect the ignition module of the retractor and connect a dummy ignition module to the ignition module
connector.
Switch on the ignition and carry out a check using the diagnostic tool.
Replace the rear seat belt retractor, driver's side, if the fault becomes stored (fault no longer declared present).
Switch off the ignition and check that the ignition module of the rear seat belt retractor, passenger's side is
correctly connected.
Disconnect the ignition module of the retractor and connect a dummy ignition module to the ignition module
connector.
Switch on the ignition and carry out a check using the diagnostic tool.
Replace the passenger's side rear seat belt retractor if the fault becomes stored (fault no longer declared
present).
Disconnect the computer and check the connections of the connector (tracks 19, 20, 41 and 42).
Attach 64-track adapter (Elé. 1717).
The CLIP or XRBAG tool absolutely must be used to measure the resistance in adapter cable J.
If the value indicated is incorrect, the wiring between the computer and the driver's side rear seat belt retractor
ignition module (C0/C3) is faulty.
Repair or replace the wiring if necessary.
The CLIP or XRBAG absolutely must be used to measure the resistance in adapter cable E.
If the value indicated is incorrect, the wiring between the passenger's side rear seat belt retractor ignition
module (C0/C3) is faulty.
Repair or replace the wiring if necessary.
AFTER REPAIRReconnect the computer and seat belt retractor, then switch on the ignition again.
Clear the computer memory then switch off the ignition.
Carry out the check again using the diagnostic tool and, if there are no faults, unlock
the computer.
Destroy any retractors that have been replaced (tool Elé. 1287).
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Fault Interpretation
88C - 61
88C
V3 MR-372-J84-88C000$072.mif
AIRBAG ACU4
Vdiag: 04
DF239
CONTINUED
CC.0 - CC.1
NOTESNone.
Lock the computer.
Disconnect the computer and check the connections of the connector (tracks 19, 20, 41 and 42).
Attach 64-track adapter (Elé. 1717).
The CLIP or XRBAG absolutely must be used to measure the proper insulation for the type of fault in adapter
cable J.
If the value indicated is incorrect, the wiring between the computer and the driver's side rear seat belt retractor
ignition module (C0/C3) is faulty.
Repair or replace the wiring if necessary.
The CLIP or XRBAG tool absolutely must be used to measure the proper insulation for the type of fault in
adapter cable E.
If the value indicated is incorrect, the wiring between the computer and the passenger's side rear seat belt
retractor ignition module (C0/C3) is faulty.
Repair or replace the wiring if necessary.
AFTER REPAIRReconnect the computer and seat belt retractor, then switch on the ignition again.
Clear the computer memory then switch off the ignition.
Carry out the check again using the diagnostic tool and, if there are no faults, unlock
the computer.
Destroy any retractors that have been replaced (tool Elé. 1287).
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Fault Interpretation
88C - 62
88C
V3 MR-372-J84-88C000$072.mif
AIRBAG ACU4
Vdiag: 04
DF240
PRESENT
DRIVER'S SEAT-CUSHION AIRBAG / LAP BELT CIRCUIT
CC : Short circuit
CO : Open circuit
CC.1 : Short circuit to + 12 V
CC.0 : Short circuit to earth
1.DEF : Configuration
NOTESIf 1.DEF, check and adjust the computer configuration.
Priorities when dealing with multiple faults: If DF240 is present with at least one of
DF077, DF065, DF210 or DF232, begin the fault finding by checking the 22-track
under-seat connector.
Special notes: depending on the type of vehicle body, this is either a lap belt
pretensioner circuit fault or seat-cushion air bag (anti-skid airbag) fault.
Never do measuring on the trigger lines with any tool other than CLIP or XRBAG.
Use the 64-track (Elé. 1717) adapter for working on the computer connector and the
22-track (Elé. 1687) adapter for working on the seat.
CO - CC
NOTESSpecial notes: correct the trigger line configuration if the
vehicle is not fitted with a driver's seat-cushion airbag / lap
belt.
Lock the computer, disconnect the computer connector and attach 64-track adapter (Elé. 1717). The CLIP or
XRBAG tool absolutely must be used to measure the resistance in the adapter cable marked B.
If the value indicated is correct, check the connections of the 64-track connector (tracks 3 and 4).
Check the connections of the 22-track connector under the seat. Repair if necessary. Attach the 22-track
(Elé. 1687) test adapter under the seat (point C1).
The CLIP or XRBAG tool absolutely must be used to measure the resistance in cable B.
Is the value obtained correct?
NO
YES
Check the seat connector connections (tracks 9 and 10).
Make sure the driver's seat-cushion airbag/lap belt ignition module is properly connected.
Disconnect the driver's seat-cushion airbag/lap belt ignition module, connect a dummy ignition
module to the ignition module connector, then again measure the resistance in cable B.
– If the value indicated is correct, replace the driver's seat-cushion airbag/lap belt module.
– If the value obtained is still not correct, replace the wiring between points C1 and C3 (seat
wiring).
Again check the connections of the seat connector (tracks 9 and 10) and of the 64-track
(tracks 3 and 4) connector.
If the fault is still present, the wiring is faulty between the computer and the driver's seat (C0/C1).
Replace the wiring if necessary.
AFTER REPAIRReconnect the computer and the driver's seat-cushion airbag/lap belt ignition module,
then switch the ignition back on. Clear the computer memory then switch off the
ignition.
Carry out the check again using the diagnostic tool and, if there are no faults, unlock
the computer. When replacing the airbag module, do not forget to reconnect the earth
on the new one. Destroy the seat airbag module or driver's seat lap belt pretensioner
if it has been replaced(tool Elé. 1287).
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Fault Interpretation
88C - 63
88C
V3 MR-372-J84-88C000$072.mif
AIRBAG ACU4
Vdiag: 04
DF240
CONTINUED
CC.1 - CC.0
NOTESNone.
Lock the computer.
Check the connections of the 22-track connector under the seat. Repair if necessary. Attach the 22-track
(Elé. 1687) test adapter under the seat (point C1).
The CLIP or XRBAG tool absolutely must be used to measure the proper insulation for the type of fault in
cable B.
Is the value obtained correct?
NO
YES
Seat wiring fault.
Replace the wiring between pointsC1 and C3.
Wiring fault between the computer and driver's seat (C0/C1).
Replace the wiring if necessary.
AFTER REPAIRReconnect the computer and the driver's seat-cushion airbag/lap belt ignition module,
then switch the ignition back on. Clear the computer memory then switch off the
ignition.
Carry out the check again using the diagnostic tool and, if there are no faults, unlock
the computer. When replacing the airbag module, do not forget to reconnect the earth
on the new one.
Destroy the seat airbag module or driver's seat lap belt pretensioner if it has been
replaced (tool Elé. 1287).
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Fault Interpretation
88C - 64
88C
V3 MR-372-J84-88C000$072.mif
AIRBAG ACU4
Vdiag: 04
DF241
PRESENT
PASSENGER'S SEAT-CUSHION AIRBAG / LAP BELT CIRCUIT
CC : Short circuit
CO : Open circuit
CC.1 : Short circuit to + 12 V
CC.0 : Short circuit to earth
1.DEF : Configuration
NOTESIf 1.DEF, check and adjust the computer configuration.
Priorities when dealing with multiple faults: If DF241 is present with at least one of
DF068, DF210 or DF232, begin the fault finding by checking the 22-track under-seat
connector.
Special notes: depending on the type of vehicle body, this is either a lap belt
pretensioner circuit fault or seat-cushion airbag (anti-skid airbag) fault.
Never do measuring on the trigger lines with any tool other than CLIP or XRBAG.
Use the 64-track (Elé. 1717) adapter for working on the computer connector and the
22-track (Elé. 1687) adapter for working on the seat.
CO - CC
NOTESSpecial notes: correct the trigger line configuration if the
vehicle is not fitted with a passenger seat-cushion airbag /
lap belt.
Lock the computer, disconnect the computer connector and attach 64-track adapter (Elé. 1717). The CLIP or
XRBAG tool absolutely must be used to measure the resistance in the adapter cable marked D.
If the value obtained is correct, check the connections of the 64-track (tracks 39 and 40) connector.
Check the connections of the 22-track connector under the seat. Repair if necessary. Attach the 22-track
(Elé. 1687) test adapter under the seat (point C1).
The CLIP or XRBAG tool absolutely must be used to measure the resistance in cable B.
Is the value obtained correct?
NO
YES
Check the seat connector connections (tracks 9 and 10).
Make sure the passenger seat-cushion airbag/lap belt ignition module is properly connected.
Disconnect the passenger seat-cushion airbag/lap belt ignition module, connect a dummy
ignition module to the ignition module connector, then again measure the resistance in
cable B.
– If the value indicated is correct, replace the passenger seat-cushion airbag/lap belt module.
– If the value obtained is still not correct, replace the wiring between points C1 and C3 (seat
wiring).
Again check the connections of the seat connector (tracks 9 and 10) and of the 64-track
(tracks 39 and 40) connector.
If the fault persists, the wiring is faulty between the computer and the passenger seat (C0/C1).
Replace the wiring if necessary.
AFTER REPAIRReconnect the computer and the passenger seat-cushion airbag/lap belt ignition
module, then switch the ignition back on. Clear the computer memory then switch off
the ignition.
Carry out the check again using the diagnostic tool and, if there are no faults, unlock
the computer. When replacing the airbag module, do not forget to reconnect the earth
on the new one.
Destroy the seat airbag module or driver's seat lap belt pretensioner if it has been
replaced (tool Elé. 1287).
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Fault Interpretation
88C - 65
88C
V3 MR-372-J84-88C000$072.mif
AIRBAG ACU4
Vdiag: 04
DF241
CONTINUED
CC.1 - CC.0
NOTESNone.
Lock the computer.
Check the connections of the 22-track connector under the seat. Repair if necessary. Attach the 22-track
(Elé. 1687) test adapter under the seat (point C1).
The CLIP or XRBAG tool absolutely must be used to measure the proper insulation for the type of fault in
cable B.
Is the value obtained correct?
NO
YES
Seat wiring fault.
Replace the wiring between pointsC1 and C3.
Wiring fault between the computer and passenger's seat (C0/C1).
Replace the wiring if necessary.
AFTER REPAIRReconnect the computer and the passenger seat-cushion airbag/lap belt ignition
module, then switch the ignition back on. Clear the computer memory then switch off
the ignition.
Carry out the check again using the diagnostic tool and, if there are no faults, unlock
the computer. When replacing the airbag module, do not forget to reconnect the earth
on the new one.
Destroy the seat airbag module or driver's seat lap belt pretensioner if it has been
replaced (tool Elé. 1287).
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - States and parameter summary table88C
88C - 66V3 MR-372-J84-88C000$080.mif
AIRBAG ACU4
Vdiag: 04
AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - States and parameter summary table
ACU4 AIRBAG STATES SUMMARY TABLE:
ACU4 AIRBAG PARAMETERS SUMMARY TABLE:
The trigger line or sensor impedance is 99.9Ω when the component is disconnected or not controlled by the
computer.STATES
TOOLDIAGNOSTIC TOOL HEADINGS
ET010
ET072
ET073
ET074
ET076
ET103
ET105
ET108
ET143
ET144Impact detected
Passenger airbag status indicator light commanded
Computer locked by tool
Fault warning light commanded
Computer to replace
Type of passenger airbag lock
Locked diagnostics power supply out of limits
Passenger airbag lock mode
Passenger airbag(s) locked
Fault present or in memory
PARAMETERS
TOOLDIAGNOSTIC TOOL HEADINGS
PR001
PR002
PR104
PR105
PR106
PR107
PR108
PR109
PR110
PR111
PR112
PR113
PR114
PR115
PR116
PR117
PR118
PR140
PR147Computer supply voltage
Vehicle type
Driver's seat sensor impedance
Line 1 impedance (Driver's seat / lap airbag circuit).
Line 2 impedance (Passenger's seat / lap airbag circuit).
Line 3 impedance (Passenger's front airbag circuit 1).
Line 4 impedance (Passenger's front airbag circuit 2).
Line 5 impedance (Driver's front airbag circuit 1).
Line 6 impedance (Driver's front airbag circuit 2).
Line 7 impedance (Driver's side curtain side airbag circuit).
Line 8 impedance (Passenger's side curtain side airbag circuit).
Line 9 impedance (Driver's front frontal side airbag circuit).
Line 10 impedance (Passenger's front frontal side airbag circuit).
Line 11 impedance (Driver's rear frontal side airbag circuit).
Line 12 impedance (Passenger's rear frontal side airbag circuit).
Line 13 impedance (Front belt pretensioners circuit).
Line 14 impedance (Rear retractors).
Number of memory zone deletions
Airbag lock circuit impedance
ACU4 Vdiag04 J84 1.0
MR-372-J84-88C000$080.mif