Leon Cupra, Immobiliser Fault or.... - Vansboy
Something else, ideas please!

A friend of Mrs Vansboy has an intermittent fault on his new Cupra.

Keeps not wanting to start, from cold or hot, call AA, 30 mins later,they come along & fires up OK.

Done this a few times, now & tonight it actually managed to NOT re-start, so it's again on its way back to the dealer.

They couldn't sort it before, so what do you think we should point them at?

Yhanks

VB
Leon Cupra, Immobiliser Fault or.... - Hugo {P}
Had a vey similar problem with my Discovery, as regulars will know all too well.

Does the starter motor turn the engine?

Do the ignition light come on when he tries to start it in the same way they would if it were behaving itself?

Do all the services (windows, radio etc) work when the ignition is on when it will not start?

If the answer to the first is NO and both the second and third is YES, I would be first looking at the starter circuit components. On the Discovery these include the ignition switch, the starter relay, the starter solenoid and the starter motor.

On the Discovery, I turned the key and could hear the starter relay clicking away, so that eliminated the switch and the relay. Thus I knew I was looking at the solenoid or the starter motor itself.

The old trick, often practised by Mini owners, is to short out the main solenoid terminals (carrying the starter motor current) with a screwdriver with the ignition on, but not whilst trying to start the car via the ignition switch. Just make sure you use a screwdriver with a well insulated handle!

If this works and starts the car, then that would suggest a dodgy solenoid. Depending on whether solenoids can be bought separately, you may be looking at a new starter motor

If the starter is turning the car and not firing it up, then the ignition is at fault (assuming its a petrol), or the stop valve on a diesel.

If the immobiliser is interlinked with the ignition, then this could be causing the problem. The old trick of testing the plugs against the block will obviously confirm presence of ignition.

The only way to test this is to try and see if you can replicate the fault without immobilising the vehicle. If it's a Passive immobiliser that kicks in after say 30 seconds, then try every 15 seconds or so, when you know the immobiliser won't have kicked in yet.

As I said earlier, the route of diagnosis would depend on the answers to the questions above.


Hugo

"Forever indebted to experience of others"
Leon Cupra, Immobiliser Fault or.... - Vansboy
Thanks Hugo,

Looks like they're blaming coil pacs.

VW type fault, IIRC!

VB