405 1.8 GLi Petrol - 'Engine Diagnosis' light

For less than the price for the 30 mins at your pug dealer, you can buy a pod to download the error memories from your ECU (Halfrauds sell em - made by Gunsons getthe correct one for your ECU/model combination) The booklet with the pod will tell you how to decode the fault codes. After about 20 engine starts after the fault has gone away so download soon after the flickering starts. Usually flickering problems are no big deal, continuous orange faults ought to be dealt with although the car should be driveable still. If the STOP light comes on then do just that and find out why.

Bob

Recently, I've had MAP sensor, throttle position sensor, and idle control valve. But it could well be anything, and you're really in the hands of the garage. Let's hope they are honest!!

Most of them !

It could be anything - you can't really decide until you know what the fault code is. Mine came on a few times when I had a split pipe to the MAP sensor - so check all the vacuum pipes are secure and split-free. I seem to remember the ECU will flag a fault if it decides the Lambda isn't working (ie, the Lambda's signal doesn't change in X time).

Thanks Bob and others.

Now slightly confused.

Does the yellow light still come on whilst driving after the fault has cleared, or does the code get stored 20 starts after the yellow light has flickered for the final time?

Yellow light comes on when ignition is first turned on, but I assumed this was just to show that the lights were working, as the other warning lights come on as well.

Booked in for a diagnostic on Saturday - local Halfords don't stock the diagnostic thingie but I will bear it in mind for future use, and Google for it as well.

Thanks Dave R

Usually, the light will flash when there is an intermittent fault, and stay on when there is a permanent fault. When intermittent, if the fault rights itself, then after a certain amount of driving cycles, or on earlier cars, 20 ignition on and off cycles, the light will stop flashing. If the fault is permanent, then the only way to get it off is to fix the fault and clear the fault code in memory.

Diagnostic test was interesting: [Report is secondhand via Number 1 Daughter]

(1) They aren't sure what the diagnostic code meant and will look into it further (!) (2) They seem to have reprogrammed the immobiliser so it won't recognise the key fob anymore, so they still have the car and we have a courtesy car. Now awaiting a slot in their busy schedule to fix it.

Perhaps the car is cursed (or perhaps the garage should be)?

Cheers Dave R

I think the garage should be! [1] There aren't that many codes on the 405 and they are all documented in their workshop books. [2] You can't programme the 405 immobiliser. The key is pre programmed from Peugeot and that is it. God knows what they have done!!