peugeot 406 warning lights! - mark(NEScotland)
The 'auto diagnostic' warning light has just appeared on the dash. (However, it didn't reappear after switching off and leaving for a few minutes)

If you read the handbook it indicates impending engine catastrophic failure and rush to your Peugeot dealer! The car is a T reg 1.8 petrol estate, 88K miles. The 'airbag' warning light has been flashing for 3 years, and supposedly 'fixed' by dealer on two occasions.

Oil and water are OK; car is serviced annually.

Could it be as suggested, catalytic converter? (or faulty electrics)

Any views on best course of action?

peugeot 406 warning lights! - SjB {P}
Just had the same warning lamp illuminate on SWMBO's 306 Sedan, which has basically the same XU7 engine as your 406.

As of a couple of weeks ago, all now fixed. The cause was the lambda probe attached to the catalyst. The reason the lamp illuminated under the conditions that it did was because the duff probe meant that the ECU couldn't maintain engine mixture within tolerance. Under all other conditions, it could. My local Pug Indy did the work, which took half an hour whilst I waited, plus some additional time for the cat to cool enough to touch.

Cost was just over £100, of which most was a genuine Pug lambda probe. Could have got the probe cheaper, and in fact I could have easily fitted it myself, but especially after they went to the trouble of reading the codes and checking the car over without charge just before Christmas, I didn't want to take the bread from their table, and asked them to do the work. The 306 costs buttons to run, and has only required this probe plus a water pump on top of routine servicing, but I'd like the guys to still be around if I need them!
peugeot 406 warning lights! - mark(NEScotland)
Thanks SjB(P).
I'll see if it stays on and contact my regular indy. Presume I've got some time to remedy it.
Similar story on this car; very reliable.
peugeot 406 warning lights! - Dynamic Dave
The 'airbag' warning light has been flashing for 3 years, and supposedly
'fixed' by dealer on two occasions.

Check the wiring going to the seat belt tensioners under the front seats. Notorious for playing up on other Pugs, and a lot of other cars, thinking about it.
peugeot 406 warning lights! - LukeMH
Hahaha flashing airbag light. Mines done that for 6 years and started when I test drove the car. They resoldered (aparently) the connectors under the drivers seat, but that only fixed it for a week. Its been back loads of times to have the under-seat connectors replaced, but it always ends up flashing again not long after. I think one set of connectors lasted 6months once, but now I don't bother.

Its probably a good thing that the airbags are dissabled. I wear glasses so dont fancy having them implanted into my face when the air bag goes off on its own (as I have seen happen with a 406 and a 306 that were owned by friends. Fortunatly both times were when the owners got out of the car and closed the doors)

Anyway, enough rambling about the airbag light. As other people have said it is most likely that your cat or lambda sensor are on their way out if the light comes on intermittently (I've had one, then the other fail on my 1996 406 and both times the engine warning light came on 'sometimes')


Value my car