ThirtyFive 21

Sounds dumb, but yes, I checked the light by replacing with a new one. Didn't work. Light worked this morning and this afternoon it decided to quit. I checked every ground I know from battery to front harness and began troubleshooting at PCB. Am I supposed to have power to the PCB at F when the ground on battery is disconnected? Seems strange that one headlight works and the other doesn't if the PCB is bad and it's all on the same wire... TM points to PCB but I have to be missing something here.

continuity checks brother. I had a few cases like this where I had to do some simple wire chasing. the power comes from the same place so I am guessing it is a problem with the power going to that light specifically. did you check and see if the high beam worked?

I got money its a ground.. right at the light... shake it.. hit it.. volt drop test are the key here... continuity... here is where you decide if you are a mech or a tech.. good luck

Did you replace just the bulb or both housing and bulb? If just the bulb, swap the housing from the opposite side that is working to non working side. Verfiry the grounding wire is clean and bolted on to the bolts that holds the housing. Simple stuff I know, but sometimes its just that simple.

Have d for a rubbing wire behind 400 amp alternator? We have had a few that the rear fan cut one or two wires and I think you have two separate wires for each headlight.

The ECVs (That's the type he's having issues with...) seem to ALWAYS burn out the lights. I've found that using the $189 LED lights prevent that from happening. Just replace the PCB with a known good and see if that fixes it. I'm willing to bet your have some short in the system up in the nose. Just trace the power to the lights. I currently have an ECV HMMWV that has a burnt out low beam but the high beam is working just fine... go figure.