sixpack_sid

I have an '86 Transam and I'm having a lighting problem. I don't know if this is a coincidence or not, but I changed the alternator a couple days ago and when I hooked the battery back up it sparked. I didn't realize that the pos wire that hooks to alt was touching the alt core & it sparked. WhenI drove into work someone told me my brake light was out. On further investigation, when I turn on the lights & running lights, they all work. But when I hit the brakes the whole pass side running & brake lights go out. It appears the back up lights come on-but dim. When I have the running lights & lights off, the brake lights work fine. When I opened the lenses up & put new bulbs in & tried them, on pass side bothofwires in bulbitselflit when the parking lights were on. When I stepped on the brakes, they all go out on pass side & both driver & pass back up lights go on. I'm pretty sure it didn't do this before. Any ideas where I should even start looking would be helpful. I'm really stumped.
Thanks!

dewey

Do you have a good wiring diagram for your brake lites and everything?

A faulty ground can cause all kinds of weird issues. Have you tied using a jumper ground for the bulb sockets? The ground wires are usually black. I don't have a good wiring diagram for your vehicle.

Can you tell if the brake-lites and turn signal work off the same filament?