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IMMOBILISER
FAULT FINDING
SUMMARY
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 01
XR25 fiche . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 02
Interpretation of XR25 bargraphs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 04
Customer complaints (petrol version) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Fault charts (petrol version) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Customer complaints (diesel version) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Fault charts (diesel version) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Conformity check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Aid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Pages
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Fault finding - Introduction
82
INSTALLATION OF XR25 DIALOGUE / DECODER UNIT
- Connect the XR25 to the diagnostic socket.
- ISO selector on S8
- Enter D56 n.56
PRECAUTION :
When carrying out the test using a multimeter, avoid using a test pin on connectors where the test pin is
of a size which could damage the clips and lead to a poor contact.
Pay attention to parts numbers on wrenches.
ERASING THE MEMORY
After repairing the immobiliser system, enter G0** on the keyboard of the XR25 kit to proceed with
erasing the memorised fault.
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Fault finding- XR25 Fiche
82
PRESENTATION OF XR25 FICHE N° 56
FI21756
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Fault finding- XR25 Fiche
82
DESCRIPTION OF BARGRAPHS
Illuminates when dialogue is established with the product computer, if it remains extinguished :
- the code does not exist,
- there is a line , computer or tool fault.
REPRESENTATION OF FAULTS (always on coloured background)
Illuminated, indicates a fault on the part tested, the associated text defines the fault.
Extinguished, indicates non-detection of fault on the product tested.
REPRESENTATION OF STATUS (always on white background)
Engine stopped, ignition on, no operator action
Status Bargraphs on the fiche are shown as they should appear, engine stopped, ignition on, without
operator action
- If on the fiche, the Bargraph is shown as
- If on the fiche, the Bargraph is shown as
- If on the fiche, the Bargraph is shown as the kit should show
either or
Engine running
Extinguished when operation or condition specified on the fiche is no longer met.
Illuminated when operation or condition specified on the fiche is met.
the kit should show
the kit should show
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IMMOBILISER
Fault finding- Interpretation of XR25 Bargraphs 82
When communication is established, deal with any fault bargraphs which may
be illuminated.
Carry out a conformity check.AFTER REPAIR
Bargraph 1 right hand side extinguished
XR25 KIT / DECODER UNIT COMMUNICATION
1
Check that lines K and L are not being disrupted by another computer.NOTES
Fiche n° 56
Check the condition of +before ignition feed fuse.
Change the fuse if necessary.
Ensure that the XR25 kit is not the cause of the fault by trying to communicate with another computer on
the vehicle (air conditioning computer, injection computer...).
Check that the ISO interface is in position S8, that the most recent version of the XR25 cassette and the
correct access code are being used(D 56).
Check battery voltage (U > 10.5 volts). Recharge the battery if necessary.
Check that the 18 track decoder unit connector is properly connected.
Check that the decoder unit is properly fed :
-earth on track A8 of the decoder unit connector.
-+ before ignition feed on tracks A9 and A1 of the decoder unit connector.
Ensure that the diagnostic socket is correctly fed.
Check and ensure the continuity and insulation of the wiring of tracks A3 and A4 of the decoder unit
connector.
If there is still no dialogue between the XR25 kit and the decoder unit, change the decoder unit.
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IMMOBILISER
Fault finding- Interpretation of XR25 Bargraphs 82
Erase the memorised fault by entering G0** on the XR25 keyboard.
Carry out a conformity check.
Check that the immobiliser system is operating.AFTER REPAIR
Bargraph 3 right hand side incorrect illumination
CODED DIESEL SOLENOID VALVE CONFIGURATION
3
NONENOTES
Fiche n° 56
Using the XR25 kit, correctly reconfigure the decoder unit.
On the XR25 keyboard, enter G22*1* for a petrol vehicle
or G22*2* for a diesel vehicle
NOTE: In the diesel version, incorrect configuration of the decoder unit does not prevent proper
operation of the immobiliser. Nevertheless, if there is a fault, the immobiliser warning light will
not illuminate.
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Fault finding- Interpretation of XR25 Bargraphs 82
Carry out a conformity check.
Check operation of the immobiliser system.AFTER REPAIR
Bargraph 4 right hand side incorrect illumination
+ AFTER IGNITION PRESENT
4
Reminder: Under normal operation :
- BG 4 right hand side illuminated ignition switch in position+after ignition
- BG 4 RH side extinguished ignition switch in a position other than +after
ignition.NOTES
Fiche n° 56
Check condition of the +after ignition fuse.
Change the fuse if necessary.
Ignition on , check for voltage of + 12 volts on track A7 of the 18 track decoder unit connector.
Are there 12 volts ?
Change the decoder unit.YES
NORepair the electrical wiring between track A7 of the 18 track decoder unit
connector and the passenger compartment fuse board.
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Check the insulation in relation to earth of
the electrical wiring between :
B2 B3
B5 A1
Is there insulation from earth?
v0406.0
IMMOBILISER
Fault finding- Interpretation of XR25 Bargraphs 82
Erase the memorised fault by entering GO** on the XR25 keyboard.
Carry out a conformity check.
Check operation of the immobiliser system.AFTER REPAIR
Bargraph 5 left hand side illuminated
CENTRAL LOCKING SWITCH (CPE)
5
Check that the central locking switch is not permanently depressed as the result of
a mechanical fault .NOTES
Fiche n° 56
Decoder
unit
Central locking
switch
YES
Change the central locking switch.
NORepair the faulty electrical wiring.
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