99 f150 - rear lights out

[GSteven]

This is odd. I was towing a trailer after verifying all lights worked properly. Took a 4 hour trip and again all lights seemed to be working OK throughout. Near the end of the trip I turned on the left blinker and it began blinking very quickly. In my experience this means I have a blown bulb. Problem is the right t/s does the same thing. Additionally I have no running lights, no hazard lights or no back up lights in the rear. All front lights work properly.

All fuses and bulbs check out ok. The brake light over the rear window works ok and the dash indicators for the turn signals works. This could only leave a bad ground I suppose. Does this sound right? Does anyone know where the ground for the rear lights is for this model?

[GSteven]

problem resolved - large connector on wire bundle had worked it's way loose. Looks as though when someone put an aftermarket trailer harness on they did not insure that the lock on this connector was engaged.