Why is my headlight fuse melting?

[Rangerpig]

Does your horn function properly?

Just for fun, try removing your 15 amp horn fuse and see if your 30 amp fuse still melts with your lights on.(I have a theory)


If you think you did not solve the loose fuse connection, maybe you could solder in wires and use a new external(out of the fuse box) fuse . I'm thinking about using a 30 amp inline fuse holder, with the wires soldered into the original fuse terminals/sockets.


Also, you could try measuring the resistance in all the headlight wires to see if you have a bad one.

Doghead, origional problem was top right fuse (circled in blue) was popping when lights turned on. I put new fuses and next issue was both red and blue (pictured) melted.
I took out 15amp horn and although neither melted, the top one (blue), popped....
I see talk about relay mod, but neither money, nor skill will allow me to do that right now. Fkn a.

Sent from my SM-G935V using Tapatalk

 

[twomorestrokes]

Old thread but I FINALLY installed the LMC harness upgrade this summer. Why did it take me so long??? Not only is it nice to not lose your headlights while booking down a back road on a black night, but to have your brake lights and turn signals work every time you need them? BONUS!

 

[Chris605]

Came to this thread because my headlight fuse was melting. Turned out to be a horn issue. It was stuck on without being able to hear it and it was overloading the fuses. Just unplugged the horn fuse and the headlights are good to go!

Thanks guys!

 

[twomorestrokes]

Trust me, without the upgrade that circuit is still overloaded.

 

[Tinstar]

Would switching to LED headlights (truck-lite) also solve the problem?
Since their amp load is much lower.

 

[cucvrus]

I have LED headlamps from truck lite. I never changed any of my headlamp wiring harnesses on any of my CUCV's. Never. I did clean a few contacts and on occasion I have removed the fuse box from the bulkhead and added a new inline fuse to get rid of the loose fuse connection. IMHO it was the loose connection that was making the heat. Not the load on the circuit. That load was fine as long as the fuse was tight in the holder. Make sense? But I never added any new Chinese wiring to the truck other than the 2 short pieces that connect the inline fuse holder to the oem wiring. It works fine and I have a trailer hooked up to the worst one I own. I got tips from CUCV electric back in the day and he told me to correct what I have and NOT cut any wiring. I corrected what I had from that point forward. Happy New Year. 2017 is just around the bend.

 

[Tinstar]

I was lucky and my first M1008A1 had a brand new GM dash wiring harness sorta installed.
No issues at all with running fan and headlights, etc.
Agree the new wiring and very tight fuses allow this.

Im still deciding about pulling the trigger on a set(s) of Truck-Lite LED headlights.
Have yet to see a truck in person with them installed.

Point is.
That could be a solution to those having issues.
Their not cheap, but cheaper than a whole/partial meltdown.
Plus much better and more light with less than half the amp draw.

The differance it made on my 5 tons was simply amazing.

 

[cucvrus]

I may have showed these pictures before. But here they are for those that did not see them. These are the truck lite LED head lamps. Direct plug in no wiring change. I like my trucks clean and free of any hacking or cut up wiring. I showed a few pictures of the clean under hood wiring. No need to add on incorrect gauge/color coded wiring. Just repair the issues that are creating the problem. Most times loose connections in the fuse box. I hope that helps sway your decision. It makes a great improvement to night driving and is easier on the oncoming traffics eyes. We have 3 CUCV's with these lights and on occasion another family member comes towards me at night driving one with the lights. Happy New Year 2017.

 

[Patattack]

Man they look good I need a pair in my m1009 and my 98 3500 those regular sealed beams suck!!!!!

 

[Tinstar]

You've posted those pics before in another thread.
I just need to see a truck with a set installed in person.
That's just me.
They have a heated version now, but it doesn't snow enough here for a set.

I'm close. Just need eyes on before I drop almost $400 a set on them. Need three sets.

 

[dependable]

Came to this thread because my headlight fuse was melting. Turned out to be a horn issue. It was stuck on without being able to hear it and it was overloading the fuses. Just unplugged the horn fuse and the headlights are good to go!

Thanks guys!

If you want your horn circuit to work again, try cutting the diode up by the horn relay (above the fuse box). It was part of the military radio suppression equipment, and known to fail, keeping horn relay on full time. There are threads on this subject also.

 

[MarcusOReallyus]

Would switching to LED headlights (truck-lite) also solve the problem?
Since their amp load is much lower.

It will probably do what you want it to do, but the circuit is just a bad design. Yes, you can get it to work, but it's still a bad design.

 

[cpf240]

... but the circuit is just a bad design. Yes, you can get it to work, but it's still a bad design.

I don't know that I'd call it a bad design, just one that fit the build budget. I'm sure it worked great when it was brand new, all the connections were clean and tight, etc. I don't think any auto manufacture builds their product to run forever, meet all possible demands, etc. They build them for an expected average life span, and nothing more.

 

[MarcusOReallyus]

It's a bad design. There are too many unrelated components running through one fuse, and there is too little headroom on that fuse. It was even a bad design by the standards of the day.

 

[KSoldier]

Just had to jump into this conversation. Thanks to all who participated, saved me a ton of elbow grease and $$ trying to diagnose the same issue and prevent future ones!
Also glad I did a search first!
BTW, Anyone near Fort Bragg NC?