Immobiliser problem - not 7 related

[dave rankin]

Twice recently my 51 plate Megane immobiliser has kicked in for no apparent reason. ☹️

 

1st time, car had been locked with the blipper, left for an hour or so and then unlocked with the blipper. Ignition key turned, all dashboard lights come on as usual, but engine wouldn't turn. Left the car for a while and tried again and it started with no problems.

 

2nd time - in a petrol station, key left in the ignition, but again same symptoms. Pushed the car away from the pumps and 5 minutes later, it started with no problems.

 

Question is, does anybody have any idea what could be causing this? I am reluctant to take it to the dealers, for them to spend hours investigating at £££££££s per hour, and then replace some expensive bit of circuitry, which might or might not have been the cause of the problem.

 

Ta muchly in advance.

 

 

 

[Miltec]

My brother had a similar issue with his 2000 Magane we spent a fortune on changing the ecu etc. never did find the issue ended up scraping the car. 😔

 

Sorry not to be of more help. ☹️

 

VX 1600 Live Axle

T440LKK

[Mike Molloy]

How do you know the immobiliser has failed?

Is there a LED telltale available somewhere?

Is the immobiliser operated by a RF remote plip or by a transponder in the ign key?

 

When my scooby ground to a halt the nice RAC man got me going by hotwiring the fuel pump. I dug out the "Thatcham Cat 1" alarm and found that one of the circuit disable relays had developed a dry joint. Soldered that up and I was away.

It was a right pain cos "Sigma" wouldn't divulge any of the operating details and all the wires were black!

[dave rankin]

I'm saying the immobiliser because the doors lock and unlock on the ignition key blipper - i.e not using the key to unlock the door - and everything seems to be normal until I turn the key, and then nowt.

 

The very nice RAC man that came out the first time it happened suggested it could be somebody with a strong WiFi signal nearby, another car being locked and unlocked or any one of a number of electrical interferences. I can understand that in a way, but for it to happen twice within a week, and never before, does seem symptomatic of something beginning to break down (and expensive!)

[Mike Molloy]

First tip - put a new battery in your RF fob.

Second tip - carry your spare fob and try that as well.

Third tip - if you do happen to park near the local mobile phone mask, the doors probably won't unlock in the first place. If you get into the car using the key, hold the plip physically as close as possible to the receiver before pressing the button.