Rear demister defogger heated screen problem

[joebongo]

Hi dudes, I've searched but can't find an answer for this one:

My rear screen demister works in the main, but I have the part either side of the 3rd brake light at the bottom of the screen non-functioning.

My friend reckons it must be on a seperate (parallel) circuit to the rest of the rear window else the whole thing wouldn't work, and to hunt down the wiring connections either in the boot (trunk) or parcel shelf to see if anything's loose, but he isn't a BMW bod - just his thoughts on how to troubleshoot this.

So does anyone have any idea where to start with this one?

I can't see any obvious breaks in the wire on the screen but will check in more detail later on.

Cheers,

Joe

[IcemanBHE]

Yes. The rear window has several tabs that are "soldered" on each side. Corrosion gets under and breaks the conection. You will need to remove the window and fix the broken connection.

[joebongo]

You will need to remove the window and fix the broken connection.

Thanks Iceman.

Far too scary for me to remove the back window :eek: (or is it not that big a job?)

Joe

[IcemanBHE]

Um. You no. Someone who does windows, not to bad. These tabs are like "glued" on with some sort of electrical conductive "stuff". A windshield shop might have seen this and fixed before. Make a call.

This is very common on E31s...oddly enough in the UK. Must be your relentless damp. Or maybe its Pilkington glass delams.