melting wires

[originalrider41]

I installed lights about a year ago and all was good. But recently iv been melting the wire coming from the battery to the relay at the relay point after seconds of the lights being on. Ive replaced all fuses, connections, splices, even good relays and the harness and the wire is still getting hot.

I know I could rewire the whole thing but the cause of the problem is really bothering me. The only thing I can think of is that running 4 lights may be too much, but wouldn't it have overheated earlier?

Any ideas as to whats causing the hot wire would help, thanks.

 

[xt master]

If the wire is getting hot it is not a big enough gauge to handle the load.One reason it could have started causing problems now could because the wire has degraded some or the bulbs are starting to go and drawing more current.

 

[JPNinPA]

Whoa!!! Hold on. Not that XT-master is incorrect about the gauge wire, but melting wire is a fire hazard. Thicker wire here may result in melting wire there or worse.
You need to share more info on what you have. You have 4 lights. How exactly are they wired and how many watts each? What gauge wire are you using? If you used them before and didn’t have an issue something changed. Did you put higher wattage bulbs in there? Take an ammeter and measure the current draw when on.

 

[Turbogus]

Yep, wire gauge, relays and fuses are of paramount importance, not to mention DON'T DROP YOUR WINCH ON THE ALUMINUM WIRE CONDUIT when you mount it up, learned that one the Marine way.

 

[SteelHeadz]

Just a thought, with all the suggestions mentioned, i would also like to add that you should check the lamp wirings from the lamp base all the way to the switch and relay. A partial short would cause the load to melt the wiring in seconds. It could be as simple as a pinched wire. If your running 4 lamps in one relay, try splitting the 2 lamps on one relay and the other two on its own relay as well. This will eliminate half the load on the amp draw from one relay.

 

[originalrider41]

I have four lights, each with their own ground, going to the relay as one (I thought it was sketchy mut mechanic said it would be fine and it was for a long time). The lights are split into pairs and each pair has its own power line. The realy then has lines going to the battery, ground and switch. The switch has its own ground and power as well.
There are two fuses and I don't remember exactly where they are and I don't want to say the wrong spot, I'm away for a bit. However I do remember I upped one of the fuses 5amp as I didn't have the exact one on hand one day, could that be the cause?
Another thought is one pair of the lights were given to me, could be daylighters, long range, whatever they're an older pair of kc's. Anyway from the start they were HOT, hot enough to melt plastic covers, that normal?

 

[originalrider41]

Ill most likely end up rewiring them and this time I'll use two relays.
And there are a couple points where wires could bent too far, I'll check when I get back.
Thanks for the input so far

 

[bobcat481]

I'm an electrician....wires don't "get bent too far". They either get scraped and shorted, or overload and overheated. One 40 amp. relay (common, off the shelf part) is plenty....keep it simple.

 

[JPNinPA]

I have four lights, each with their own ground, going to the relay as one (I thought it was sketchy mut mechanic said it would be fine and it was for a long time). The lights are split into pairs and each pair has its own power line. The realy then has lines going to the battery, ground and switch. The switch has its own ground and power as well.
There are two fuses and I don't remember exactly where they are and I don't want to say the wrong spot, I'm away for a bit. However I do remember I upped one of the fuses 5amp as I didn't have the exact one on hand one day, could that be the cause?
Another thought is one pair of the lights were given to me, could be daylighters, long range, whatever they're an older pair of kc's. Anyway from the start they were HOT, hot enough to melt plastic covers, that normal?

That sounds okay. The 5amp fust is likely for the switch and should have no baring on this issue. How far a run from the battery to the relay Then from the relay to the lights? If you could find out what size teh other fuse is and we might be able to figure out the light wattage.