Page 324 of 363

v0406.0
IMMOBILISER
Fault finding - Fault Chart (diesel version)82
AFTER REPAIRCarry out a conformity check.
Check that the immobiliser system is working correctly.
Erase fault memory G0**.
Fault Chart 2IGNITION ON, IMMOBILISER WARNING LIGHT FLASHES
PERMANENTLY (impossible to start)
None.NOTES
no See Fault Chart 1.
Switch on the ignition.
Connect the XR25. Use fiche n° 56, selector
on S8. Enter D56.
Is there communication between the XR25
and the decoder unit?
yes
no Replace the fuse if necessary.
yes
Check the condition of the antenna ring.
Is the fuse in good condition?
no
Refer to the chart for bargraph 4RH in the
section "Fault finding -Interpretation of
XR25 bargraphs ".
yes
no Carry out the programming operation if the
unit is new , otherwise, replace the decoder
unit .
Switch on the ignition and check that
bargraph 4RH is illuminated .
Is Bargraph 4RH illuminated?
yes
A
Switch on the ignition and check that
bargraph 19RH is extinguished .
Is Bargraph 19RH extinguished ?
82-27
Page 326 of 363

Check continuity and insulation from earth
and 12 volts of the wiring between :
2 earth
3
+AVC
4A2
Is the wiring in good condition ?
v0406.0
IMMOBILISER
Fault finding - Fault Chart (diesel version)82
AFTER REPAIRCarry out a conformity check.
Check that the immobiliser system is working correctly.
Erase fault memory G0**.
Fault Chart 2
CONT 2
B
no Repair the faulty wiring .decoder
bornierantenna
ring
yes
yesReplace the antenna ring .
yes
no Replace the decoder unit .
Check for voltage of + 12 volts on track A2 of
the decoder unit (decoder connector
disconnected and antenna ring connector
connected ).
Is this voltage present?
yes
Replace the key.
Switch off the ignition and wait until the
immobiliser warning light flashes
(immobiliser active ). Set the XR25 to pulse
sensor mode (button "G",
input on terminal "Vin").
When turning on the ignition again, check for
a pulse on track A2 of the decoder unit (test
with decoder unit and antenna ring
connectors connected).
Is there a pulse?
82-29
Page 327 of 363

Check the condition of the wiring between :
8A6
and the solenoid feed
(12 V and earth)
Is the wiring in good condition ?
solenoid valve
coded electronic
unit connector
v0406.0
IMMOBILISER
Fault finding - Fault Chart (diesel version)82
AFTER REPAIRCarry out a conformity check.
Check that the immobiliser system is working correctly.
Erase fault memory G0**.
None.NOTES
no Repair the wiring.
yes
no Replace the decoder unit .
decoder
bornier
yes
no
Replace the solenoid valve coded electronic
unit or refer to Workshop Repair Manual
section "changing the decoder and key kit".
Replace the decoder unit .
yes
XR25 connected , use fiche n° 56.
Carry out a mechanical check of the solenoid
valve .
-- Ignition off, enter G23*.
- Switch on the ignition. The valve should
open and close several times in 30 seconds
(listen).
Does the valve open and close for
approximately 30 seconds ?
Set the XR25 to pulse sensor mode (button
"G", input on terminal "Vin"). Ignition on,
check for pulses on track A6 of the decoder
unit connector (test with decoder unit and
solenoid valve coded electronic unit
connectors connected).
Are there any pulses?
Fault Chart 3IMMOBILISER WARNING LIGHT REMAINS ILLUMINATED FOR
LONGER THAN 30 CONSECUTIVE SECONDS , IGNITION ON
82-30
Page 328 of 363

v0406.0
IMMOBILISER
Fault finding - Fault Chart (diesel version)82
AFTER REPAIRCarry out a conformity check.
Check that the immobiliser system is working correctly.
Erase fault memory G0**.
Fault Chart 4WHEN THE IGNITION IS TURNED ON, THE IMMOBILISER ILLUMINATES FOR 3
SECONDS, THEN EXTINGUISHES, BUT THE VEHICLE WILL NOT START
None.NOTES
yes
Solenoid valve coded electronic unit
is not faulty.
Refer to fault finding for the diesel engine.
Connect the XR25. Use fiche n° 56. Carry out
a mechanical check of the solenoid valve .
- Ignition off, enter G23*.
- Switch on the ignition. The valve should
open and close several times in 30 seconds
(listen).
Does the valve open and close for
approximately 30 seconds?
no
no
Replace the solenoid valve .
yes
Remove the solenoid valve coded electronic
unit . Check the condition of the solenoid
valve. Ignition off , connect +12 volts to the
solenoid valve . Now try to start the vehicle.
Will the vehicle start ?
Replace the solenoid valve coded electronic
unit .
82-31
Page 329 of 363

v0406.0
IMMOBILISER
Fault finding - Fault Chart (diesel version)82
AFTER REPAIRCarry out a conformity check.
Check that the immobiliser system is working correctly.
Erase fault memory G0**.
Fault Chart 5IMMOBILISER WARNING LIGHT REMAINS PERMANENTLY ILLUMINATED (even
when ignition turned off ) OR REMAINS PERMANENTLY EXTINGUISHED
Check that decoder unit programming has been properly carried out.NOTES
no Replace the fuse.
yes
Check the condition of the +before ignition
fuse.
Is the fuse in good condition?
no Repair the wiring.
yes
Check continuity and insulation from earth
of the wiring between track A5 of the 18
track decoder unit connector and the
instrument panel .
Is the wiring in good condition?
Carry out the following tests to determine the
faulty component :
- If the immobiliser warning light is
illuminated , disconnect the 18 track
decoder unit connector and check that
the immobiliser warning light
extinguishes,
- If the immobiliser warning light is
extinguished , connect track A5 of the
decoder unit connector to a vehicle earth
and check that the immobiliser warning
light illuminates.
Does the immobiliser warning light
illuminate correctly during the test?
no Replace the instrument panel .
Replace the decoder unit .
yes
yes
Check that bargraph 5LH is extinguished .
Is bargraph 5LH extinguished ?no
Refer to the chart for bargraph 5LH in the
section "Fault finding - Interpretation of
XR25 bargraphs "
82-32
Page 340 of 363

1EC761.0
AIRBAG - SEAT BELT PRETENSIONERS
Fault finding -Introduction
CONDITIONS FOR THE APPLICATION OF THE CHECKS DEFINED IN THIS FAULT FINDING
The checks defined in this fault finding should only be applied to a vehicle when the fault bargraph is
illuminated, indicating that the fault is present on the vehicle at the time of checking. Only a computer
fault will require replacement of the computer, whether the bargraph is permanently illuminated or
flashing .
If the fault is not present but simply memorised, the bargraph flashes and application of the checks
recommended in the fault finding section will not allow the origin of the fault to be found. In this case,
only a check of the wiring and the connection of the component in question must be carried out (it is
possible to test the wiring concerned in fault finding mode to try to obtain permanent illumination of the
bargraph ).
TOOLING REQUIRED FOR OPERATIONS ON THE AIRBAG AND SEAT BELT PRETENSIONER SYSTEMS :
- XR25 (with minimum XR25 cassette N° 16).
- XRBAG the updated N° 3 version (with the new measuring lead and its adaptors as well as the 30 track
adaptor for operations on the computer connector).
REMINDER:
When carrying out an operation on the airbag/seat belt pretensioner systems , it is essential to lock the
computer with the XR25 command G80* to avoid all risk of triggering at the wrong time (all firing lines
will be inhibited). This operating mode will be indicated by illumination of the warning light on the
instrument panel.
Never carry out any measuring operations on the airbag and pretensioners trigger lines with equipment
other than the XRBAG.
Before using a dummy ignition module, ensure that its resistance is between 1.8 and 2.5 ohms.
Only 30 track connector computers with airbag(s) function are able to be tested with the XR25.
Computers with the pretensioner function only must be checked with the XRBAG by following the checks
described in the fault finding section.
The ignition must be switched off, then on again to make the warning light extinguish following erasure
of the memory using the command G0**.
88
88-1
Page 345 of 363

1EC761.0
AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - XR25 fiche
MEANING OF BARGRAPHS
FAULT BARGRAPHS
(always on coloured background)
If illuminated, indicates a fault on the product tested. The associated text defines
the fault.
This bargraph could be :
- Illuminated : fault present.
- Flashing : fault memorised.
- Extinguished : fault absent or not found.
STATUS BARGRAPHS (always on a white background)
Bargraph always located on the top right hand side
If illuminated , indicates establishment of dialogue with the product computer.
If it remains extinguished :
- The code does not exist.
- There is a tool, computer or XR25 / computer connection fault.
The following bargraph representations indicate their initial status :
Initial status: (ignition on, engine stopped, no operator action)
Indefinite
illuminated when the operation or the condition specified on the
fiche is met.
Extinguished
Illuminated extinguished when the operation or the condition specified on the
fiche is no longer met.
ADDITIONAL SPECIFICATIONS
Certain bargraphs have a *. The command *.., when the bargraph is illuminated,
allows additional information on the type of fault or status to be displayed.
or
88
88-6
Page 346 of 363

1EC761.0
AIRBAG - SEAT BELT PRETENSIONERS
Fault finding - Interpretation of XR25 bargraphs
Bargraph 1 right hand side extinguished Fiche n° 49
Code present1
The computers which only control the operation of the seat belt pretensioners do
not have XR25 fault finding (check to be carried out with XRBAG).
When communication is established, deal with any illuminated fault bargraphs.AFTER REPAIR NOTES
Check the presence and condition of the airbag fuse .
Check the condition of the computer connector and the condition of the connections.
Check that the computer is correctly fed :
- Disconnect the airbag computer and fit the 30 track adaptor of the XRBAG.
- Check and ensure the presence + after ignition feed between the terminals marked
Earth and +after ignition feed.
Check that the diagnostic socket is correctly fed :
-+ Before ignition feed on track 16.
-Earth on track 5.
Check the continuity and insulation of the lines of the diagnostic socket / airbag computer connection:
- Between the terminal marked L and track 15 of the diagnostic socket .
- Between the terminal marked K and track 7 of the diagnostic socket .
If dialogue is still not established after these various checks, replace the airbag computer (consult the
section on "Aid" for this operation).
Ensure that the XR25 is not the cause of the fault by trying to communicate with the computer on
another vehicle .
Check that the ISO selector is in position S8, that the latest XR25 cassette and the correct access code are
being used.
Check the battery voltage and carry out the operations necessary to obtain the correct voltage (10.5 volts
< U battery< 16 volts).
88
88-7