I'm not sure how the wiring is setup for a civic, but with the integra if you look from behind the car at the hatch, the wiring is in the upper right corner... There is a "protective" cable cover around the wires where they pass thru from the hatch to the frame... Here the 3rd light and the wiper cables pass thru... I had to remove the "protective" cable cover and inspect... There was not much wire to work with... But after A bit of pulling I could see that most of the cables were frayed... I had to pull the interior decor strip from the hatch to give me enough cable to solder and heat shrink it back together...

It was a perplexing bitch to find the root causes... But after talking with other gen1 Teg owners this is a common problem...

The other thing to look at is the brake switch, make sure it is wired properly... A volt meter will tell you this... On an 86 Teg it is located at the pedal... Such that the switch unlatches when the brake is pressed away from it...

Beyond that, get a volt meter w/ continuity checking ability and have lots of patience... Trace it from the source (switch) back to the light... It is one of 2 things, the switch or a short...

That's about the best advice I can give...