My 2007 Hummer H3x the passenger headlight goes off when I turn brights on. I have cleaned the connector, I tried new bulbs, I even got new LED plug and play headlights, same issue. Every time I turn on the bright lights on the passenger light goes off.
However, when I purchased the Hummer, LOW BEAM DID NOT WORK on the passenger side. I purchased new headlight bulbs, once I changed the bulb, the bright did not work but the low beam worked fine. I thought maybe bad headlight bulb, so I got another bulb and the same issue,
IF ANYONE CAN HELP ME, I would greatly appreciate it. PLEASE!! Thank You!

 

Welcome to HF.

Check the wire harness to the bulb connector and make sure the pins from the truck wire side are all fully embedded in the headlight connector. When you say you "have cleaned the connector", did you use electrical contact cleaner spray both sides and let it dry before plugging in the bulb?

Assuming you are using H13 bulbs, correct?

I am thinking you stretched the harness in your first bulb change and the pins are not all the way in and making proper contact. Just a guess.

 

Headlamp Circuit


Relay 70 provides (-) to both the high and low beams. Relay 75 provides (+) to both individual bulbs. If relay 70 were not working you would not be able to switch either lamp to high beam. If relay 75 were not working you would not be able to turn on the headlamps at all. If fuse 40 or 41 is blown you will lose all functionality (high and low bean) of the associated bulb. From your description all of these components are working.

You have a wiring issue as Doc Olds stated. Make sure none of the pins backed out of the connector and none of the wires are broken.