Hmmwv electrical problem

Changed out all the side markers and lights in my Hmmwv to all new lights.

My driver side tail light was working originally fine but rear markers were not. Found a bed ground on the markers and they seem to work fine however now the driver side tail light does not work at all. #21 wire is getting power. Passenger light works fine without any problems.

All the lights were purchased from mid west military.

What mfgr is the lamp? Most need good ground on both mounting screws.

Its not called out in the TM, but we always used serrated washers to insure a proper ground. And made sure everything was clean and use a bit of sand paper to ensure metal to metal contact.

NDT said:

What mfgr is the lamp? Most need good ground on both mounting screws.

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It’s from Midwest Military Depo. When I plug in OEM works great but then clearance light from the side does not work.

Guyfang said:

Its not called out in the TM, but we always used serrated washers to insure a proper ground. And made sure everything was clean and use a bit of sand paper to ensure metal to metal contact.

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used sand paper on the plate and washer

Also look for chafed or broken wires in the loom. I‘ve had that problem and it gave me intermittent fits until I realized the problem.