My 82 T/A has had a lot of things changed along with the engine and transmission (not by me). The back up lights have never worked. The trans is a t-10 4 spd it has what looks like places to plug in wiring but I cant find the wires any where to hook up, Im wondering if I might be missing an entire harness(probably wouldnt be big) for the back up lights, the brake lights and park lights work fine. There are some female plugs under the hood I thought might be them but there isnt even any power to them. I just took out my carpet to replace it which exposes a lot of wires so I am going to try to trace them from the tail lights back cant find wires under the car so maybe there inside. Anyone got any ideas!

 

I'm assuming a t-10 has the same b/u switch a t5.
The backup lights are not on a compex circut but, tied into the factory harness can be a nightmare to hunt down.
The b/u lights are powered by the blue wire comming off the turn signal flasher relay (which is powered off the Turn B/U fuse), the blue wire then runs to the bulkhead connector (next to the brake booster) on the firewall and to the switch on the trans. From there the green wire runs right back to the bulkhead, back inside, to the rear, back outside and to the reverse lights.
The blue wire should have constant +12v with the key in the 'run' position and the green only when the trans is placed in reverse. Probe the wiring with a multimeter (or 12v tester light) at certain points to see where the power starts/stops (if there's any at all on the circuit) and most likely you'll find your problem. Could be something as silly as both reverse bulbs being burnt out...

 

Thanks I will try it.

 

Were is the b/u switch on the tranny? Thanks!!!