running lite problem

[dumpsterdan]

i have a 63 d100 and my running lights dont work and the right brake light doesnt work. the head lights work but not the back lights. i couldnt find a fuse box do these years even have one. also theres a small black box under the the truck by the tailgate that recently fell off and the wires are the same color as the wires off the tail lamps.what is this box?

[wideblock]

id be willing to bet the black box used to house trailer connection wireing and is probably the reason your rear lights dont work. id check the headlight switch as well, if its bad, your headlights will work but nothing else, 2 seperate circuits thru the switch. try clening the firewall connections as well, they are simple plug ins, if they get corroded a bit, they wont work. but first things first, id start at the rear and trace the harness back and be sure the wires arent burnt, cut, or broken anywhere along the line. fron running lights are most likly a bad ground. they ground thru the grill. so you have the monuting points where the housing hits the grill, and where the grill is bolted to the rad support that can all loose ground. i would run a small jumper wire from the housing to the neg side of the battery as a test to see if they work.

[dumpsterdan]

i dont know what the black box was but it was ripped out so i reconnected the wires and everything works beautiful.thanks for your help

[wideblock]

been there, done that. my truck had a wireing nightmare under the bed when i got it. when i threw in the towel, and decided trying to figure out whats wrong wasnt working, and just rewired the whole thing, everything has been golden since.