As far as i've been able to tell, my B5 A4 Fwd doesn't have a separate Comfort Control Module (CCM). I've pulled up the carpet under the driver's seat and found nothing there. The issue i'm having is that the overhead lights don't automatically come on. They work fine when i manually switch them on and the footwell lights come on when the door opens, but no matter which door is open, the overhead lights never come on automatically. I've read that they may get power from the central locking module, does anyone know if this is true? I'm planning on pulling the module and checking for corrosion like i've seen in some other posts. Anyone have any other ideas what might be going on? Thanks all!

 

Nothing, huh? Does anyone know where the overhead lights get automatic power from? I'd like to do some testing with my multimeter but don't even know what i'm looking for without a pinout.

 

Here's an update: i pulled the central locking pump to check for water damage, and it looks great inside and out. Pulled the dome light, and i have +12 volts constant and good ground when it's switched on, no ground when on auto mod and doors open.

 

Is there a switch in the door that isn't flipping letting the light know that they're open?

I have no idea how to check for that unfortunately.

 

The car shows that all 4 doors open correctly. Footwell lights light up just fine, and dome/map lights turn on when switched manually. It's strictly a problem of the dome lights not getting a ground signal when the doors open.

 

I had this problem with my '97. I just went to the junkyard and picked up a new overhead lamp. You may be overthinking it, sometimes I guess they just go bad.

 

Got it fixed! After several days of continuity testing and an alldatadiy subscription I found a broken pin inside a connector. There's a brown wire with white stripe going from the dome light all the way back to the central locking pump in the trunk. There was some corrosion in the connector behind the driver's side kick panel and somehow the pin for that wire was broken off at the base. Cleaned up the connector with some baking soda and water, spliced in a new length of wire bypassing the connector on that wire, and i'm square! Hooray for freak electrical problems!