944#447

Went 2 miles to the gas station last night, shut off the headlights and the car. Got back in and the switch was stuck off. I popped it out and the switch and harness was hot. Switch was partially melted to the harness connector at the top right pin in the photo. Can't tell the pin number its too melted.

I ordered a new switch from pelican. What could cause this? I've read up that it is a somewhat common problem. Shouldn't a fuse have blown somewhere? Should I add a fuse? What do I do about the harness connector?

orig944

The terminal number is 56, not that it matters. The switch got old, the contacts got corroded and had more resistance. The current running through it heated up the contacts, which conducted back to the connector, melting stuff. Interestingly, because the contact was in series with the bulbs, the circuit resistance increased, lowering current (and bulb brightness.) Fuses cannot fix this. Unfortunately, the connector housing is no longer available, so if you want to replace it, you need to scrounge a used one.

Preventative measures include lower current LED headlights, or rigging relays under the hood to move the high current path away from the switch.

Zirconocene

Agreed with the above; look up posts on a headlight relay harness. I made one for myself but there are inexpensive commercial options available that people give good reports on.

Good luck

Tiger03447

Good luck with the depinning. Take a LOT of pics before you start this procedure. Be sure the numbers are visible also. There are about 11-15 wires in the plug. Getting the right wire into the right hole is paramount for further operation of the switch and all that is downstream of it. Good luck!!😀

DHS928

On eBay look for the Hella Dual Relay kit, I lets you put all the power to the lights through it and your switch only turns on the relay. I put mine on the left side behind the light and after removing the air filter box you can connect the relay power to the alternator. The light plugs are high temp ceramic plugs, just make sure you keep the wires away from the arms that rotate the buckets so they do not interfere. I run 55/100 bulbs no issues.



Hella 329.317-001 H4 Headlamp Headlight Relay with Wiring Harness 90/100W S2u

Tiger03447

The early cars, like yours and mine have many poorly fused or not-at-all fused circuits. Look way up over your accelerator pedal while looking at all of the white wrapped harness, snaking around under the dash, and will see a black, small rectangular box with two white square plugs going to it. This is the fog light relay. It is a double relay. A new one costs about 35+_ dollars. Change out this 40 year old POS and replace it. It’s probably original, and they stick. If that happens you will have an under dash pile of melted wires,bare conductors stick out all over, and a GIANT bunch of problems that I am facing now. This circuit is unfused also. The later cars corrected this with the later fuse/relay panel. Hope this help some.😀