Electrical issue? Got a stumper here!!

[qwert98]

I’ve got a stumper here. I have a 2003 Z4 (50k miles) and have an intermittent recurring issue. Seems to happen after it rains. The issue is that the following things stop working until I unhook the battery for a couple hours so the computer can reset: Top, windows, radio(powers on but no sound), signal lights (flash on the car, but not the dash), AC.

Once it resets, it’s fine until the next time. Could be days, weeks or months later.

Any ideas???

[brettski]

I'd start by trying to isolate an area of the car to focus on. You can do this by taking the car out onto your driveway, get the garden hose an spray a section of the car at a time, get it as wet as you think would reasonably simulate the rain that has been causing the problem, not too much more though. Once you've done that, hop in the car and go for a drive or do what you'd normally do to reveal the problem. If nothing happens move onto the next section of your car, and keep repeating the process until you have a possible area to start focussing on, I suspect that its going to be a blocked drain probably under hood/bonnet which is backing water up into an electronic box. See how you go and let us know what you find.
Cheers

[qwert98]

Great idea, I will try that. I will look for evidence of water backing up also. Already replaced convertible top pump due to flooding...
I am sure this is not a problem unique to my car - anyone have a similar experience?