Laguna Starting Problems fixed on 2003 1.9 Diesel F9Q

So yesterday we had a customer in with Renault Laguna starting problems on a 1.9 diesel 2003. The customer had called the AA who advised him it might be a problem with the key/immobiliser. The customer also reported the car was cutting out while driving.

Lagunas have the key card with push button start so customer was having to do the push button – wouldn’t start – take off button – try again, procedure and it would maybe start after half an hour.

As we do car keys ,it was first passed to Zaif, our ‘Key Man’, who checked was whether this is an immobiliser key problem. The Key Card seemed ok. Possibly something with the card reader? doubtful.

It then got taken into the workshop and inspected by Lukas, our mechanic. At first Lukas suspected it could be the crank position sensor which he knew can be a problem with these – a tricky one to diagnose because the fault doesn’t always show up on the readers.

After deep contemplation, meditation and whatever else Lukas does before he comes out with something brilliant…Lukas announced that he’d fixed it.

The answer?

ECU? Engine Management Fault? Wrong and Wrong.

The answer was Fuse Contact Corrosion. Yep…there’s some fuses and relays which are linked to the fuel pumps and if they go, or the connection is not right for any of the fuses or relays which are linked to the fuel supply…you’ll have a starting/cutting out problem. Car now starts fine.