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Matt, Mechanical Engineer
Category: Renault
Satisfied Customers: 22764
Experience:  BEng hons Mech engineering, in auto industry 22 years
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My 55 plate modus died but I do not know whether it's an

Customer Question

My 55 plate modus died but I do not know whether it's an immobilser problem or a flat battery. After work I went to open it remotely and nothing happened at all. The central locking was in place so accessed vehicle via key on passenger door.The red immobilser light was flashing fast and the green indicator lights also but no actual lights working. All the warning lights came on and then blanked out except the annoying clicking of the immobiliser light.Next day I tried to use the emergency spare key which did unlock the car but failed to start it or change anything. Occasionally the clock would blip up but otherwise the clicking immobilser only. Recently it had a new indicator stalk fitted as the wipers stopped working and also the headlights came on when the indicators were activated. The horn didn't work directly after this work was carried out which was a week before the dead car episode. The car remains unlocked. The only thing that I did on the morning of said death was to push in the cigarette lighter. I do not know if this was faulty asI don't smoke and I didn't notice if it had popped out.Could this have drained the battery or is it an immobiliser problem.
Submitted: 1 year ago.
Category: Renault
Expert:  Matt replied 1 year ago.


I'd 1st try charging the battery up and if its over 5 years old then the battery may need replacing as low battery voltage will give all sorts of odd faults

Also check that the alternator is actually charging the battery in the car by taking a battery voltage reading with the engine off then another with the engine running. The 2nd reading should be higher than the 1st and climbing steadily. And also check that the alternator is secure to the engine as this provides the ground for the charging circuit and make sure that the engine / gearbox earth strap is secure and the contacts are clean and bright.

if the alternator appears not to be working - take it to a electrical specialist and ask them to test it as sometimes you can replace just the diode pack and this will repair the alternator without requiring replacement

Expert:  Matt replied 1 year ago.


do you still need help?

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