on my 86 iroc, if all the lights are off, and you hit the brakes, the brake lights come on.. as well as the dash lights, shifter lights, and the parking lights. but, if you have your headlights on while driving, the brake lights are always on and when u press them, it barely gets brighters. any ideas?

 

kind of sounds like a floating ground to me. had a similar problem on my 89 RS. check your wiring diagrams and look for a common ground/grounds for all of those circuits and make sure its tight, not broken, corroded, ect..

hope this helps

 

Has anyone wired in any additional (non-factory) lights? Alot of times, someone will try wiring in aditional interior lights (like underdash lights), and in an attempt to get them to light with the opening of the door AND the operation of the light switch, they'll end up with a situation where power backfeeds through. The door switch switches a ground, the headlight switch switches a positive, and thus makes a mess unless relays or diodes are used.

If there's any of that, remove it, and see if everything goes back to normal again. Then you can rewire the extra lighting correctly if you desire to keep it.

 

i think it's a ground issue somewhere. lights are stock however the highmount has no wiring to it