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Jeep Patriot Headlight Mystery

Hi

The right headlight is not working, however it does work on the Highbeam setting. I switched the bulb, same problem. I looked and switched the fuses, this also did not fix it,

I am stumped, I would be grateful for any ideas about what is causing this problem and how to fix it!

thanks

Jeff

Jeep Patriot
Model-Year ?

CSA

Depending on the year, there should be a ground for the light to the chassis the needs cleaning. Or it goes to the body module. The second is not cheap.

There may also be a relay for each individual low-beam headlamp. You can test by swapping the L & R ones and see if the problem switches sides. These relays would likely be in the fuse box under the hood, but your owner’s manual might list where they are. I doubt the ground is bad if the lamp lights on high beam–it would be hard to believe there’s a separate ground for high and low beams. Though it could still be a wiring problem.

Double (triple?) check that you changed the correct bulb. I had a similar problem – I had swapped the wrong bulb.

I think you will find that you have a common ground wire to both the low and the high beam sockets or at least terminating to one wire. Then you would have a hot wire to the high beam and a different hot wire to the low beam. Suspect a problem with the socket, hot wire, or ground if its a separate ground. You can use an ohm meter or just run a test wire right to the bulb to figure out which wire, then start looking for why. Might just need to freshen up the connections. There should be a separate relay for the high and another one for the low, but they would or should run both left and right. So if one side works, most likely not the relay.