So a previous owner of this car (86 GT) monkeyed with the headlight wiring, installed a switch to manually lower the headlights, overriding the LCM. I looked into it and checked some stuff, and I know what he’s done. Eventually I’ll move to Gen II headlights, but for now his wiring isn’t too bad. Either way, after I returned all the wiring to as it was before I messed with it, my parking/running lights now do not work at all. I checked the fuse, and it’s fine. When I turn headlights or even parking lights on, none of the running or taillights work. Brake lights and headlights still operate but that’s it. I don’t know if what I was doing messed it up, or wiring somewhere else came loose. (it’s been driven pretty hard since)
