Audi A6 avant 2.5 tdi central locking problem

[mhobson]

I have a 1999 A6 Avant with a very irritating problem. The doors lock automatically at 15 mph but from time to time when driving over a bump or twist in the road, the car unlocks itself and turns all the interior lights on. I then have to stop the car, turn the engine off, open and close the drivers door and lock and unlock the car a few times with the key remote to reset it. It sounds like a bad connection, but I do not know where the central locking unit is to see if it is there. Is there an impact sensor which would automatically unlock the doors in case of an accident, but if so would that also discharge the airbags. There have been many other instances of bad connections in the car already. Any constructive advice would be appreciated. Regards, Michael

[audinut]

Hi Michael,

Does this post -> http://www.vwaudiforum.co.uk/forum/showthread.php?t=14074 ring any bells? May be related ....

[Peter D]

The central locking system control unit is located in front of the driver's seat beneath the floor covering. Check this area for water ingress. I suspect it is a faulty switch in a door lock assembley. The Air bag sytem if triggered does unlock the car but the air bags would go off. Regards Peter

[mhobson]

Dear Peter, My car is LHD, is the unit still on the drivers side. Compared to my previous A6 1996 which forever had water ingress especially the tailgate, this car seems very dry throughout. Thanks, Michael

[Lex Luthor]

The symptoms you describe are as if the ignition key was removed from its lock.
There is a switch there to detect the presence of the key and perhaps it has become intermittent.

[mhobson]

Dear Peter and Audinut, I have read the previous thread as suggested about interior lights coming on, but with that car the door open warning illuminated, but this has never happened with my car, just interior lights and doors unlocking, last night on a short journey I unlocked the doors immediately after they locked at 15 mph and after about two miles there was a relay clunk and the interior lights came on and I had to reset the system as in my initial post, I plan on finding the control unit and checking the connections to it. Dear Lex, the ignition lock is a thought but would that not turn the radio off, which doesn't happen. Regards, Michael

[Peter D]

In your case it is on the drivers side. The manual is LHD biased so on mine it is in the passengers side. Regards Peter