headlight switch overheating

[Pilot199]

Has anyone experienced the headlight switch assembly overheating while on?

Mine ('92 model) actually melted a part of the large plastic plug/harness. I've replaced the harness & all works properly but the switch assembly still gets hot & I suspect that it will melt it again. FYI, none of the fuses or breakers involved have ever blown.

Thanks,

Gary

 

[Mr. Alligator]

I have noticed that my original 1997 headlight connector had mild burn marks, so I switched out the head light switch with a salvage unit.

I would replace your switch ASAP. Maybe unplug the switch (hopefully, you don’t have to drive at night) until you can get replacement.

Never had fuses blown out either.

Good luck!

 

[Pilot199]

I have noticed that my original 1997 headlight connector had mild burn marks, so I switched out the head light switch with a salvage unit.

I would replace your switch ASAP. Maybe unplug the switch (hopefully, you don’t have to drive at night) until you can get replacement.

Never had fuses blown out either.

Good luck!

That sounds like a good idea. Thank you.

 

[timtimtimajim]

Look into getting a headlight harness with relays like this: Heavy-Duty Headlight Harness

You could even build your own harness if you had to. Adding the relays in will take the load off the switch.

 

[CDW6212R]

Look into getting a headlight harness with relays like this: Heavy-Duty Headlight Harness

You could even build your own harness if you had to. Adding the relays in will take the load off the switch.

Ditto, install a relay to power the headlights.

The issue is full current running through the wiring to the dash, connectors, and the switch. Over time it degrades the wiring and the connector terminals, plus the switches. High current circuits have always done that and older vehicles have those problems. The headlight circuit is a primary one that is easy to fix if the OEM circuit items still function.

Simply install a relay near the load, feed it with a fused main power wire, and trigger the relay with the original circuit load wire.

The same thing happens with the AC control unit in the dash, the high current sometimes causes a loss of voltage reaching the AC clutch. Same fix, install a relay under the hood near the AC clutch side, and cut the original clutch power wire, running it to trigger the new relay. I did that exactly with my 1991 Lincoln Mark VII, which has an EATC dash controller. The EATC would have to be repaired if it didn't produce enough power to trigger a relay. But it did, so adding a relay meant I didn't have to touch the EATC, an I haven't. If that EATC was installed into another Mark VII, the AC clutch would not engage, but with the new relay in that first car, everything works fine.

 

[~X~]

I installed relays & #10 wire. My brights are brighter and my dims are worse than ever. But the basics are covered, less load on the headlight switch.

 

[CDW6212R]

I installed relays & #10 wire. My brights are brighter and my dims are worse than ever. But the basics are covered, less load on the headlight switch.

There you might need to inspect the circuit again for the dim low beams, see if there is some burned wire or terminal that is bad enough it needs replacing. The low beams use a different circuit than the high beams, I'd want a relay for both of them.

 

[Mr. Alligator]

Don’t the headlights/headlight switches have an OEM relay? Doesn’t this cover it?

 

[~X~]

. The low beams use a different circuit than the high beams, I'd want a relay for both of them.

I have a relay on each circuit, high & low beam. My lenses are clear and polished, new Sylvania bulbs. My sockets were cleaned when I made the harness. I've read here on the subject & others have said the same thing, low beams were no better after the increase in wire size and relay added. I'm not too bummed about it, polishing the lenses inside and out made a huge difference and my headlight switch should last a good, long time.

 

[CDW6212R]

Don’t the headlights/headlight switches have an OEM relay? Doesn’t this cover it?

I believe the 1995 up Explorers do, but the thread poster has a 92 and those didn't. The 2nd gen's automatic light circuit uses a relay for sure, I'm not sure about the manual light switch. I have seen posts about that 1995+ switch having electrical burn damage on the connector it plugs into.