Hello, this is my first post to this awesome subaru site. I own an '80 GL wagon

with origionally a single range four speed (just blew my third tranny). I have this

problem with my headlights, it makes the 25 amp circut hot enough to melt the plastic surrounding the fuse. I can't find a short anywhere. The parking lights

don't effect the fuse, just when the headlights are on. The headlights still work

(the fuse element sags, but hasn't blown yet). The things that I assume could be the problem besides a short i can't seem to find could be a bad switch or headlight relay. Anybody have any problem like this?

What wattage are the headlights pulling? If they're uber-mega-photon-blasters, they could be drawing a lot.

 

Also, make sure the connections for the fuse are clean. Corrosion on a contact will cause resistance, which will make heat with current flow.

 

-=Russ=-

Welcome! yes the switch could be your problem. Goto junk yard and pull one and see if that fixes it. Had it happen on a sube except it was brake light switch That had an internal short that was melting fuse block.

Also check the grounds on the headlights to make sure they're clean cause if its pulling too many amps, it'll get the wires, fuse, plastic, etc. hot enough to melt.

check the fuse :cool:

use only OEM fuses from the junk yard!

a good fuse will melt the filament, not the plastic

I agree about checking the connections at the fuse. Having a poor connection there will cause this problem. The wiring on the backside may be the problem. If the fuse contacts can't be repaired you can install another fuse with a pigtail and bypass the old position.

The headlights are stock replacement lamo Sylvana Extravision(not the halogen).I don't think they'll draw too much amps. The problem fuse is a 25 amp(powers half the fuse block, the other 25 amp fuse powers the other half of the fuse block) the headlight fuse seems fine, no melting. I will check out the ground and the switch. I recently purchased a parts car, an '83 GL wagon with an EA81 dual range four speed(the one posted in marketplace on craigslist(parts car for $250 in Mountlake Terrace, severe front damage)), I will be borrowing parts off that one(totally complete car, well taken care of WOW!!!!). I'll check the headlight switch and the ground. I will get back with the results(unless y'all see a big backyard car fire on the news he he). Thanks.

I'll also scotchbrite the fuse connection. i'm using buss fuses.

I had this same problem on my 78 Brat. Or at least the owner before me did. They had put a big ceramic resistor on the headlight wire right before the fuse box. The fuse box was obviously damaged. I went to my local junk yard and got a replacement headlight switch and fuse box. That was over a year ago and the problem has never come back. So that is where I would start.

My money is on corrosion/rust ect. on and around the terminals of the fuse box

 

If the fuses aren't blowing then the problem isn't too much current, you have what is known as a hot joint which is caused by a high resistance somewhere in the circuit, probably in your fuse box

 

Get a little ammery cloth and clean the contacts on the offending fuses

 

 

Hope this helps

 

Gannon

The wire between the fuse box and the headlight switch gets pretty warm too.The headlight wires in the engine bay are cool.

The wire between the fuse box and the headlight switch gets pretty warm too.The headlight wires in the engine bay are cool.

 

Going by that, I would take a look at the connections between the fuse box, and the light switch. Loose fitting, or corroded terminals will cause excess heat. If nothing is found with the connections, I'd swap the light switch itself.

As someone stated before, the problem area is where the damage is occuring. If the ground or lightswitch were a problem then they would be heating up. When excessive resistance occurs in a high current circuit like this then a voltage drop appears across that resistance. This is basically acting like a heater element, but you don't want that to happen at your fuse connection. The connection resistance should be close to what the feed wire resistance is. I would check the connections to the fuse contacts. Since it sounds like too much damage has now occured to the connection and you may have to replace the fuse connection with a replacement in-line type fuse. The fuse contacts may not be repairable and will have too much resistance no matter what you do to them. Here is an example of a fuse holder that will handle the current and has the proper size 12ga. wire for the current load.

 

Inline ATO/ATC 12 Ga. Fuse Holder Inline ATO/ATC 12 Ga. Fuse Holder

Inline fuse holder for ATO/ATC fuses. Rated to a maximum of 30 amps capacity. Features a 'Write-in' space to easily identify the circuit. Includes 12 ga. red wire and fuse cover. Does not include fuse.