2000 A4 B5 interior lights not working automatically

[daniel214214]

Hi all!

I have an annoying issue with my facelift A4 B5 Avant. The interior lights do not come on automatically (on door open).
- I can turn them on manually, and they all work that way (front and rear)
- the footwell lights are both working automatically (left and right), so the door sensors are good
- my car does not have a comfort module under the seat, only the central locking pump module in the back

I've read all the possible forum posts about interior lights not working that I could find but nothing seems to help my case.

My suspicion at this point would be the central locking pump electronics, or maybe the wire that runs from the pump to the dome light - but I'm not really sure where that runs exactly.

Anyone had a similar issue that they've managed to solve?

Many thanks!

[daniel214214]

All right, I have finally managed to solve this.

The brown-white wire that goes from the central locking module (CLM) to the interior lights (giving the bulbs a ground connection so as to turn them on) passes through a few connectors. There's a grey connector (T15o) in the A pillar connector station (left side of driver's footwell, behind the plastic trim) - I'm not sure how water found it's way in there, but the pin for the interior lights has completely corroded away. I've connected the wire outside of the connector, and all is working now!

As I have now also found out, the fading of the interior lights is controlled by the CLM itself..

[fouregon]

Just wanted to say good job on the diagnosis and fix, and good info to know about the wire pathing and the CLM controlling the fade. Thanks for concluding your own post!


Charles.
‘01 Avant 1.8t Tip