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Headlight switch hot to touch

Morrie01

Morrie01

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Drove about 40mins to town today with the lights on. Went to turn them off and the switch was hot to touch.
Ive only owned the car for about 3 weeks so working through issues as they arise.
I played with the dimmer knob about a week ago and blew the fuse so havent touched that since.
Obviously thinking the first place to start is to have a look behind the cluster and check all connections and then go from there.
Any ideas.please?
 
Hot = resistance. Possibly a bad connection in the switch itself. Others here may have more knowledge on where to look first but I would test the resistance of the headlight switch with a multimeter. It should be 0 ohms.
 
Ideally maybe, but nothing has zero resistance, but the main point here is the lower resistance, the less heat generated with current flow. And as a side note, resistance also in most cases increases with temperature, and so does oxidation of most metals which also slowly increases the resistance in any connection, leading to even higher temperatures. One of the small advantages of using larger gauge wire, it acts as a passive heat sink to help keep nearby connections cooler.
 
Yes, check the connections and “probably” need a new headlight switch or rebuild yours. That’s a dangerous place to have a short since there’s no fuse to save your wiring in the headlight circuit
 
PurpleBeeper said:
Yes, check the connections and “probably” need a new headlight switch or rebuild yours. That’s a dangerous place to have a short since there’s no fuse to save your wiring in the headlight circuit
Click to expand...
I also installed a relay kit, and felt uncomfortable running such a high current power lead unfused to the front of the likely to be damaged area even in a minor front end fender bender. So I fused it.
Typically, I changed course mid project and converted to lower amperage LEDS. :BangHead:

P1010397 headlight fuse.JPG
 
Don’t overlook the firewall bulkhead connections in your search. I apply De-Ox cleaner and a light application of No-Ox (light bulb grease) on the spade of any connection I take apart as a precaution to connector resistance. But blowing the fuse with the dimmer adjustment could indicate the interior of the switch is in bad shape.
 
PurpleBeeper said:
Yes, check the connections and “probably” need a new headlight switch or rebuild yours. That’s a dangerous place to have a short since there’s no fuse to save your wiring in the headlight circuit
Click to expand...
Don't all Mopars in our eras have a circuit breaker in the headlamp switch?
Mike
 
I would certainly just replace the switch, not all that expensive and readily available on E bay for $ 50.00- $ 60.00 US range. Inspect wires going to the switch connector for signs of heating or poor contact, also inspect the wire to connector pin crimps. Same goes for bulkhead connector.
 
Thanks for all the advice guys. I live in New Zealand so normally in bed when you guys are posting.
Will let you know what's up once I get time to have a look.
Need to sort the water pump bearing and one of the exhausts first before I tackle this switch.
 
Heat at the headlight switch? Too much headlamp current for what the stock switch and wiring was designed for. Replacing the switch isn’t going to fix it. What headlamp type are you running? Likely have some wire warming going on as well in the stock 16ga headlight wiring and experiencing a high level of voltage drop at the lamps. Relays are the solution, get all that current off the stock wiring, dimmer switch, and bulkhead terminals altogether. Really don’t need to buy a kit, fairly easy install from scratch if possessing any rudimentary electrical skills.
 
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