airbag off RENAULT SCENIC 2011 J95 / 3.G Air Bag ACU4 - Seat Belt Pretensioners Workshop Manual

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Introduction
88C
88C - 3V3 MR-372-J84-88C000$010.mif
AIRBAG ACU4
Vdiag: 04
3. REMINDERS
Procedure:
To run diagnostics on the vehicle's computers, switch on the ignition in fault finding mode (+ after ignition forced
setting):
– vehicle card in card reader.
– Press and hold start button (longer than 5 seconds) with start-up conditions not fulfilled,
– Then connect the diagnostic tool and perform the required operations.
+ After ignition feed cut-out is performed as follows:
– Disconnect the diagnostic tool,
– Press the start button twice briefly (less then 3 seconds),
– See that the + after ignition feed has been cut off by checking that the computer warning lights on the instrument
panel have gone out.
Faults:
Faults are declared to be either present or stored (depending on whether they appeared in a certain situation and
have disappeared since, or whether they remain but are not diagnosed within the current context).
The present or stored state of faults should be taken into consideration when the diagnostic tool is used after the
+ after ignition feed (without acting on the system components).
Deal with present faults according to the procedure specified in the Interpretation of faults section.
For stored faults, note the faults displayed and follow the instructions in the "Notes" section.
If the fault is confirmed when the instructions in the Notes section are applied, the fault is present. In this case, deal
with the fault
If the fault is not confirmed, carry out basic checks. Check:
– the electrical lines which correspond to the fault,
– the connectors for these lines (for oxidation, bent pins, etc.),
– - the resistance of the faulty component,
– the condition of the wires (melted or cut insulation, wear).
or use the fault finding procedure to check the circuit of the faulty component.
Conformity check
The conformity check is designed to check the states and parameters which do not display any faults on the
diagnostic tool when inconsistent. This phase therefore:
– diagnosis of faults that do not have a fault display, and which may correspond to a customer complaint.
– checks that the system is operating correctly and that there is no risk of a fault reappearing after repairs.
This section gives the fault finding procedures for states and parameters and the conditions for checking them.
If a state is not behaving normally or a parameter is outside permitted tolerance values, you should consult the
corresponding fault finding page.
Customer complaints – Fault finding charts
If the diagnostic tool check is correct, but the customer complaint persists, it should be dealt with according to the
customer complaint.IMPORTANT
The left-hand and right-hand Xenon bulb computers are powered when the dipped headlights are lit. Fault finding
procedures can only be carried out on them after the ignition has been switched on in fault finding mode (+ after
ignition imposed) and the dipped headlights are on.
A synopsis of the general procedure to follow is provided on the following
page in the form of a logic flow chart.
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Introduction
88C
88C - 5V3 MR-372-J84-88C000$010.mif
AIRBAG ACU4
Vdiag: 04
All faults requiring replacement of a computer for thorough fault finding with the appropriate tools. The diagnostic
sheet must be filled out during the process and indicate the findings for the warranty refund.
6. SAFETY INSTRUCTIONS
All work on components requires obeying safety rules to prevent physical damage or human injury:
– Make sure the battery is properly charged to avoid damaging the computers with a low charge.
During operations on the airbag/seat belt pretensioner systems it is vital that you lock the computer using
the diagnostic tool to prevent any risk of accidental triggering (all the ignition lines will be inhibited). The
locked mode is signalled when the Instrument panel warning light comes on.
If it is impossible to connect the fault-finding tool, switch off the ignition, remove the system power fuse,
and wait at least 2 seconds for the reserve power capacity to discharge.
Never measure the airbag or pretensioner trigger lines with any device other than XRBAG or CLIP's "Airbag
and pretensioner wiring harness check".
Before using a dummy ignition module, ensure that its resistance is between 1.8 and 2.5 ohms.
While working, make sure the computer power supply does not drop below 10 V. WARNING!
5. FAULT FINDING LOG
WARNING:
A properly documented diagnostic sheet is required for all monitored part (computer-type)
reimbursements or Techline calls.
IT IS THEREFORE COMPULSORY TO FILL OUT A FAULT FINDING SHEET EVERY
TIME
A FAULT FINDING OPERATION IS PERFORMED.
WARNING
Airbag and pretensioner destruction and disposal is subject to national legislation.
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding – Replacement of components
88C-12
88C
V3 MR-372-J84-88C000$040.mif
AIRBAG ACU4
VDIAG No.: 04
AIRBAG - SEAT BELT PRETENSIONERS
Fault finding – Replacement of components
REPLACING THE AIRBAG COMPUTER
BEFORE REPLACING ANY COMPUTER, YOU ARE REQUIRED TO CONTACT YOUR
TECHLINE.
So that the failure of the returned computer can be analyzed, the use of command RZ001
"erase fault memory" when DF001 "Computer" is present or stored is officially prohibited.
The airbag computers are sold in locked mode to avoid all risk of accidental triggering (all ignition lines are
inhibited).
The locked mode is signalled when the airbag fault warning indicator lights up on the instrument panel.
Follow this procedure to replace an airbag computer:
– Ensure that the ignition is switched off.
– Replace the computer.
– Modify the computer configuration if necessary.
– Enter the VIN into the computer with diagnostic tool command VP010 Write VIN.
– Switch off the ignition.
– Carry out a check using the diagnostic tool.
– Enter the After Sales operation date with diagnostic tool command VP008 Write last After Sales operation
date.
– Unlock the computer only if no faults are indicated by the diagnostic tool.
After an ACU4 computer has been replaced with a RC5 computer, it is also necessary to replace the impact
sensors. The ACU4 sensors are incompatible with the RC5 computer.
Note:
After the airbag computer is replaced, if the engine no longer starts, restore the injection operation by applying the
following procedure:
– Run command RZ001 to clear the faults from the injection computer memory (even if no present or stored faults
are declared).
– Switch off the ignition and wait for loss of dialogue with the injection computer.
– Drive for 1 minute at a speed greater than 21 mph (35 km/h) to restore the operation of the steering column lock.
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Interpretation of faults
88C-19
88C
V3 MR-372-J84-88C000$071.mif
AIRBAG ACU4
VDIAG No.: 04
AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Interpretation of faults
DF001
PRESENT
OR
STOREDCOMPUTER
NOTESSpecial notes: So that the failure of the returned computer can be analysed, the
use of command RZ001 "Erase fault memory" when DF001 "Computer" is
present or stored is officially prohibited.
Replace the airbag computer (see the Replacement of components section for this procedure).
AFTER REPAIRDeal with any faults declared by the diagnostic tool.
Clear the computer memory.
ACU4 Vdiag04 J84 1.0
MR-372-J84-88C000$071.mif MR-372-J84-88C000$071.mif

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Interpretation of faults
88C-20
88C
V3 MR-372-J84-88C000$071.mif
AIRBAG ACU4
VDIAG No.: 04
DF002
PRESENT
COMPUTER SUPPLY VOLTAGE
1.DEF: Micro-cut
2.DEF: Values beyond tolerance
NOTESSpecial notes: Use the 22-track adapter (Elé. 1685 when working on the computer
connector (cable 1).
Carry out the operations necessary to obtain the correct voltage supply to the computer: 10.5 V ± 0.1 < correct
voltage < 16 V ± 0.1.
– Check the battery charge.
– Check the charging circuit.
– Check the tightness and the condition of the battery terminals.
– Check the computer earth.
– Check the condition of the computer + locking connections.
AFTER REPAIRClear 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.
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Interpretation of faults
88C-21
88C
V3 MR-372-J84-88C000$071.mif
AIRBAG ACU4
VDIAG No.: 04
DF010
PRESENT
FAULT WARNING LIGHT CIRCUIT
1.DEF: External diagnostics (instrument panel signal)
2.DEF: Consistency (dashboard indicator light state signal / airbag request)
NOTESSpecial notes: none.
Apply the fault finding procedure relevant to this fault in the instrument panel fault finding information section.
AFTER REPAIRClear 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.
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Interpretation of faults
88C-22
88C
V3 MR-372-J84-88C000$071.mif
AIRBAG ACU4
VDIAG No.: 04
DF028
PRESENT
PASSENGER AIRBAG STATUS INDICATOR LIGHT CIRCUIT
1.DEF: External diagnostics (instrument panel signal)
2.DEF: Consistency (dashboard indicator light state signal / airbag request)
NOTESSpecial notes: none.
Apply the fault finding procedure relevant to this fault in the instrument panel fault finding information section.
AFTER REPAIRClear 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.
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Interpretation of faults
88C-23
88C
V3 MR-372-J84-88C000$071.mif
AIRBAG ACU4
VDIAG No.: 04
DF034
PRESENT
COMPUTER LOCKED
NOTESSpecial notes: none.
Using the diagnostic tool, run command VP007 to unlock the airbag computer.
AFTER REPAIRClear 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.
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Interpretation of faults
88C-24
88C
V3 MR-372-J84-88C000$071.mif
AIRBAG ACU4
VDIAG No.: 04
DF039
PRESENT
DRIVER'S SIDE SENSOR CIRCUIT
CO: Open circuit
CC.0: Short circuit to earth
1.DEF: Communication disrupted
2.DEF: Sensor internal electrical fault
3.DEF: External diagnostics
NOTESSpecial notes: Use the 64-track adapter (Elé. 1717) when working on the computer
connector.
CO - CC.0 - 1.DEF
NOTESNone.
Lock the computer using the command on the diagnostic tool.
Check that the driver's side sensor is connected correctly and check its connections.
Check the condition of the connections on the computer (tracks 27 and 28).
Check the condition of the 64-track connector (locking system, connections, etc.).
Check the continuity and insulation of the connections between:
Bornier (Elé. 1717) terminal 27 Track 1 sensor connector
Bornier (Elé. 1717) terminal 28 Track 2 sensor connector
2.DEF - 3.DEF
NOTESIf the fault is still present, check whether the sensor fitted is
compatible with the airbag computer connected to the
vehicle. If not, order the sensor specifically for the airbag
fitted.
Replace the driver's side sensor.
AFTER REPAIRClear 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.
ACU4 Vdiag04 J84 1.0

AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Interpretation of faults
88C-25
88C
V3 MR-372-J84-88C000$071.mif
AIRBAG ACU4
VDIAG No.: 04
DF040
PRESENT
PASSENGER SIDE SENSOR CIRCUIT
CO: Open circuit
CC.0: Short circuit to earth
1.DEF: Communication disrupted
2.DEF: Sensor internal electrical fault
3.DEF: External diagnostics
NOTESSpecial notes: Use the 64-track adapter (Elé. 1717) when working on the computer
connector.
CO - CC.0 - 1.DEF
NOTESNone.
Lock the computer using the command on the diagnostic tool.
Check that the driver's side sensor is connected correctly and check its connections.
Check the condition of the connections on the computer (tracks 61 and 62).
Check the condition of the 64-track connector (locking system, connections, etc.).
Check the continuity and insulation of the connections between:
Bornier (Elé. 1717) terminal 61 Track 1 sensor connector
Bornier (Elé. 1717) terminal 62 Track 2 sensor connector
2.DEF - 3.DEF
NOTESIf the fault is still present, check whether the sensor fitted is
compatible with the airbag computer connected to the
vehicle. If not, order the sensor specifically for the airbag
fitted.
Replace the passenger side sensor.
AFTER REPAIRClear 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.
ACU4 Vdiag04 J84 1.0