82A-3V1 MR-372-J84-82A000$010.mif
ENGINE IMMOBILISER
Fault finding – Introduction82A
SVT
Vdiag No.: 04
4. REMINDER
Procedure
To run fault finding on the vehicle computers, switch on the ignition. Connect the diagnostic tool and perform the
required operations.
SCENIC II and MEGANE II:
To run fault finding on the vehicle computers, switch on the forced + after ignition feed.
Proceed as follows:
LOGAN, SANDERO, DUSTER, MASTER II ph2 and ph3, THALIA 2/SYMBOL 2, CLIO II F6, KANGOO VLL
To run fault finding on the vehicle computers, switch on the + after ignition feed.
Proceed as follows:Switch on the forced + after ignition feed:
– with the vehicle card in the card reader,
– press and hold the Start button (longer than 5 seconds) with start-up conditions not fulfilled,
– connect the diagnostic tool and perform the required operations.
Switching off the forced + after ignition feed:
Press the Start button twice briefly (less than 3 seconds).
Ensure that the + after ignition feed has been cut off by checking that the computer warning lights on the instrument
panel have gone out.
For vehicles with key/radiofrequency remote control unit,
switch on the ignition with the key.
82A-6V1 MR-372-J84-82A000$010.mif
ENGINE IMMOBILISER
Fault finding – Introduction82A
SVT
Vdiag No.: 04
5. FAULT FINDING PROCEDURE (continued)
Wiring check
Fault finding problems
Disconnecting the connectors and/or manipulating the wiring may temporarily remove the cause of a fault.
Electrical measurements of voltage, resistance and insulation are generally correct, especially if the fault is not
present when the analysis is made (stored fault).
Visual inspection
Look for damage under the bonnet and in the passenger compartment.
Carefully check the fuses, insulators and wiring harness routing.
Look for signs of oxidation.
Physical inspection
While manipulating the wiring, use the diagnostic tool to note any change in fault status from stored to present.
Make sure that the connectors are properly locked.
Apply light pressure to the connectors.
Twist the wiring harness.
If there is a change in status, try to locate the source of the fault.
Inspection of each component
Disconnect the connectors and check the appearance of the clips and tabs, as well as the crimping (no crimping on
the insulating section).
Make sure that the clips and tabs are properly locked in the sockets.
Check that no clips or tabs have been dislodged during connection.
Check the clip contact pressure using an appropriate model of tab.
Resistance check
Check the continuity of entire lines, then section by section.
Look for a short circuit to earth, to + 12 V or with another wire.
If a fault is detected, repair or replace the wiring harness.
