Hey all,

I have an '86 with the high brake light in the rear. I have the "my rear defroster turns on when I brake" problem. In order to fix this, I checked, sanded, and dielectric greased all the connectors for the rear defroster, and the grounds near the latch. When that didn't work, I took apart the high brake light, which wasn't working either, replaced all the bulbs, and greased that all up. The brake lights were still not working and the defroster still turned on. Today I tried to remove the whole setup and investigate, but in the process tore up alot of plastic (I didn't WD40 first and the grounds spun and tore up all the plastic).

Anyways, is the top brake light the likely cause, as I thought? Where else could there be a problem? I have only tried to use the rear defroster a few times recently but I don't think it was functioning, because the hatch stayed frosty after a long warm-up time.

Also, does GM still stock that upper brake light housing, or is it discontinued?

Thanks all,
-Jack

 

well i know on my 86 it will only turn the defroster on when the third brake light it burnt out...as soon as i change it im all good...otherwise i dont know whats wrong

 

I tested the row directly to the battery and all of em lit up. I'm gonna swap the 906's in today and see if it makes a difference. I really need a new housing now, though.

Also, I read something about how there's a switch in the brake pedal for that light only. If that switch went bad, would it cause this behavior?

Thanks again,
-Jack

 

couldnt hurt to check it out......and actually im not sure but is ur liscense plate light blown? check that out because when my third brake light blown the light that lights up my plate blew 2 so that may have something to do with it.....im not that familiar with the electronics of these cars yet so im just speaking from experience

 

Well, no dice. I want to replace the upper housing and the grounds for it, are they available aftermarket, or do I have to search junkyards? I think the grounds are the problem, and the hex caps have been bored out by a previous owner, so I can't tighten them up all the way.

Thanks, -Jack