No Low Beams - Only High Beams

[1stgear]

Please help! I have LED lights on my m998. When I went to drive it last night the low beams had stopped working on my LED headlights. Only the high beams work. Both low and high worked fine the last time I drove it. Any ideas on what the issue could be?

 

[tomelroy]

foot switch could be bad...test for power at lights. If you have power to the low beams could be the led lights

 

[swiss]

Just a reminder to everyone,

I spent 3 hours chasing down my low beams being out on my CUCV. After testing everything and replacing some components I decided to check the bulbs, duuuuuuuuuuuuuu

Guess what both low beams in the bulbs had burned out around the same time.

 

[MaverickH1]

My M1123 had both low beams burned out as well on non-LEDs. The only way to be sure is to test for voltage at all of the points. The easiest thing to do is to unplug right at the back of the lights and check for voltage on the appropriate wires (look for the wiring diagrams in Volume 3 of the publicly available Maintenance Manual). If you get no voltage for the low beams at the headlight connector, trace back to the next easiest to get to which is the floor switch. If you DO get voltage for the low beam right at the headlight connector, then game over and replace the headlights. Make sure the floor switch outputs voltage at both high and low beams and that the correct wire is plugged in to the correct place. If there's no voltage coming out of the floor switch on the low beams, you should be able to stop there since your high beams work.

I'm not looking at a wiring diagram to do this troubleshooting.... but it's from memory because I had to do the same thing on mine.

If you want to be completely thorough also add continuity checks to the wires to make sure there isn't a short or breakage happening somewhere.

 

[1stgear]

I'm betting it's the dimmer switch since I recently had that unscrewed so I could replace the floor mat and do some painting. I'll start there! Thanks to all.

 

[MaverickH1]

I'm betting it's the dimmer switch since I recently had that unscrewed so I could replace the floor mat and do some painting. I'll start there! Thanks to all.

haha okay, but it's a heck of a lot easier to check the wire right at the headlight first! But I suspect you are right if both went out at the same time like that.

 

[Retiredwarhorses]

The floor dimmer switch is 3 screws, I would start there...most likely the issue.

 

[Action]

Instead of checking for voltage at headlight, just switch the low and high beam wires on the back of the headlamp, inside the hood is easy.
if you unplugged the foot switch, you may have pushed a plug to the side of the boot, so no contact for dims.

 

[86humv]

Please help! I have LED lights on my m998. When I went to drive it last night the low beams had stopped working on my LED headlights. Only the high beams work. Both low and high worked fine the last time I drove it. Any ideas on what the issue could be?

I've had many led headlights.....over 50, and about 10 % of them, the low didn't work .

 

[tage]

The low on mine (leds) don't work.
I don't feel like opening mine up to fix them, so I live with it.
It's not street driven anyways so it doesn't bother me.

 

[86humv]

There's no fixen them LED's....have to get another.

 

[1stgear]

"if you unplugged the foot switch, you may have pushed a plug to the side of the boot, so no contact for dims."
That's exactly what it was. I had pushed a plug to the side as the new mat was thicker. I remember having a tough time getting that foot switch in there.
Thanks for all the replies. I would have never checked the foot switch!