Zumkopf

I've had this happen several times now: if I replace the battery, or just try jump-starting a dead battery, the sunroof (without being commanded to) opens itself all the way and then jams in the rearward position. The dealer's top mech had apparently seen this before, and attributed it to the sunroof ECU misreading the voltage. Or some nonsense like that.

The immediate fix is to crank the sunroof closed manually. If your manual crank doesn't work (mine didn't), then you can drop the sunroof motor (three torx screws and it's out), pull the roof forward by hand as far as you can, then jam a screwdriver in the rear part of the track and pull it forward (this forces the rear articulated leg to bring the roof all the way closed and pop up into the sealed position). Then reinstall the sunroof motor. You may need to repeat this once to get the cycle set right (on the first post-removal cycle, sometimes it stops partway open).

The longer term fix isn't a fix, really. Just remember: if you have to replace the battery or jumpstart the car, pull the sunroof fuse first (IIRC it's the sixth fuse on the lowest (brown) fuse carrier, in the right footwell fuse box). Then do what you need to do electrically. When all is well with the car, reinstall the sunroof fuse. That will prevent the problem occurring.

Marty
'98 A8Q S8 suspension

Always Overcharged

Curious -good info thanks-Did the last owner die in the car????

Zumkopf

Possibly the prior owner, or a prior incompetent wrench, stripped the hex socket the crank fits into. But the dealer mech couldn't close it either.

The first time this happened, they were going to charge me $760 for a sunroof motor replacement, and I'd have paid it too, but they also said they "just couldn't fit it in" until the following week. Rain was predicted for the weekend; they wouldn't even agree to keep it inside. So I had a go at it and came up with this repair procedure. They lost $760 by postponing a job that would have taken them ten minutes.

Zumkopf

This "possessed by demons" sunroof problem occurs in other Audis too. It's rare, but common enough that the mech seemed to know exactly what caused it, and explained it with confidence. Of course, his suggested fix was to replace the sunroof motor. I'd rather drop and refit the motor, save the money, and redo the fix if I forget to pull the fuse. [I now put a note on top of the battery to remind myself to pull the fuse.]