i have a 97 a4 2.8 quattro. my rear defrost doesnt work. i have checked the window itself to see if i can find any breaks in the heating lines or anything and they all seem to be perfect. but i cant find where the wiring from the switch goes to in order to actually heat up the lines. like on most cars, there is a metal bracket on the side and you see the wiring going to it and the bracket touching the heating lines. all i see on mine are the lines and thats it. anybody got any ideas on this??

 

someone like jestnomen or redgoat might have an answer for you.....just wait until the gods arrive.....

 

Have you checked your fuses? You can find the two connectors on the window heater by removing the trim around the window (c piller). There should be two of them, one on each side of the window. I would start from there with a multimeter to check for power. That should help you isolate the problem.

 

yeah i figured the connectors would be in that trim panel, i just wanted to make sure before i go ripping things out. i have checked all the fuses in the main fuse box in the drivers door side of the dashboard and they are all good. are there any fuses anywhere else?

 

Not that I know of. It might be #26?? Check the back of the fuse cover too.

 

but there's nothing else in the system right? its just a simple switch, fuse, wiring, and the heating elements right? so if the fuse is good and i'm not getting power, the switch is bad and there is nothing else to worry consider?

 

Well if you pull the connectors off and read voltage then the switch and wiring harness is good. Then you can assume there is a break in the heating element. I've seen patch kits to fix those, but can't remember where exactly. If you don't get any voltage then you need to work back in the system to issolate the problem. Just because the fuse isnt burned or visably blown doesn't mean it isn't. Again use a multimeter to check the impedance across the terminals.

 

yeah i know how to do all that. i'm an electrician as my job lol but i was just wanting to make sure there were no other components in the system to check. thanks for your help

 

Honestly I'm not sure, I don't have a schematic of defrost system. Good luck!