Brake light short
 

My brake light works when the light switch in on but when i step on the brakes, the 2nd filament doesn't light up. So, the light stays the same when I apply the brakes. :crazy:

I thought the bulb housing was bad, corroded, so I got a new one from LMC, and the problem is still there.

Anyone have this problem? I don't have a circuit tester. Going to get one though and try to chase down the problem. Any tips??

Thanks!

Re: Brake light short
 

The way I'm reading this it's only one side correct ? If so start at the rear of the truck where the harness plug is, Check for power on two wires with all other lights off and while the brake pedal is pushed. You could un-plug the switch at the pedal and install a jumper wire to activate the lights. If you have voltage at the plug trace the wires in the rear harness looking for any that are broken or pinched.

Re: Brake light short
 

Yes, pass. side only. Drivers side brake light works fine.

Thanks, Rob! I'll get out and try it out tomorrow.

Re: Brake light short
 

just an update. Finally was able to look at the truck and traced the short to a old trailer wiring harness from the previous owner. Had the cheap "snap on" quick connects for the harness. Looked OK on the outside but when I unsnapped one of them, it was corrodded pretty bad! I just took them all off and re-connected the main lines. Pretty easy.