Headlight issues

[flareside_thunder]

Went out in the woods tongith with 6 other trucks...go stuck 3 times and never used my headlights...just the markers. Anyways, after we left there we went to eat at Chili's and all was fine with my headlights. On the way home however, after turnign a corner my highbeams went dead...low beams work fine but high beams are gone on both sides....can't even pull the high/low lever back to get em to come on...Doesn't work.....So, I've got bulbs in it that are less than 2 months old.....I actually called Chris to ask him which bulbs he uses and that's what I bought...50 bucks and I've got the heavy duty headlight harness from LMC Truck.... any thoughts on where to start looking? Obviously I'll check the filamants in both sides tomorrow....

 

[Skandocious]

Yeah checking the filaments is your first logical step. Would be strange for both of them to burn out at once... Perhaps one was already out and you didn't know it.

One thing about the higher power bulbs is that they do not last as long as the low power (obviously). They burn hotter so the lifetime is shorter, says so right on the packaging. Even still, you should be getting a lot more than 2 months life out of them-- especially the high beam filaments because they don't get used as often. I almost wonder if that LMC harness is somehow causing the problem. What exactly does it do? I thought it just added relays to the headlight power circuits so that the power for the headlights wasn't traveling directly through the dash switch. Did it somehow make your headlights brighter?

 

[smokey]

I had the same thing happen on several of my trucks. I would be checking the multi-function switch.
They have a tenancy to go bad under normal use but when you add the brighter bulbs they can't that the extra current draw and fail prematurely.

 

[blacksnapon]

....can't even pull the high/low lever back to get em to come on...Doesn't work.....

I think you answered your own question.......multi function switch.

 

[Skandocious]

I think you answered your own question.......multi function switch.

Well if the high beam filaments burned out then the multi function switch also wouldnt do anything when pulling it back. If the filaments look healthy then I'm with you-- multi function switch is probably the culprit. My next guess would be possibly a wiring problem with that relay kit from LMC.

 

[flareside_thunder]

Ahhhh didn't think of that I was dog arse tired...now thinking about it...it's could be the high beam side relay in the harness couldn't it? And yes the hrness is made to draw it's power straight from the battery and not through the switch. It actually did my my lights brighter.