headlight fuse blowing
 

My 15amp fuse that powers the dash lights and headlights kept blowing so i replaced it
with a 20amp fuse so i could drive home, that stopped the fuse from blowing but as i was driving i could smell something plastic burning. would that be the cause of the fuse blowing or would it be because the 20amp fuse is too strong?

I think this might have started happening since i connected my efan. In the engine bay there's a green cable near the battery that i've used a wire from to turn on the relay for the fan. However the fan was continuing to work even when the headlight fuse was blown, so that means the relay isn't connected to the same power as the headlights doesn't it?

Id suggest to look at the electrical fsm and find out what that green wire was for kicks.

It could be one of the bulbs or so in the dash is causing it, I'd take a look back there, ouch that could of started a fire :X, next time I'd drive without dash lights.

What wire is usually used to power a fan relay? I'll just swap it over to a different one and see if that fixes the problem.

I've disconnected the fan and I replaced the headlights and tail lights and the fuse is still blowing. What else could be causing it?

there is a wire grounding out someone. sounds like you may need to track down this problem. theres a reason that fuse keeps blowing

I don't know what kind of car your working on, but the HEADLIGHT fuse is in the engine bay and is a 30A fuse.

What fuse are you blowing and where is the location of that fuse. Fuse box covers are found in the FAQ thread at the top of this page.

The headlight switch uses power from the HEADLIGHT fuse in the engine bay to control the up/down function of the headlight assys (along with the Retract fuse) but just puts a ground on the headlight relay in the engine bay to actually turn the headlights on/off.

If your blowing the fuse that controls the side/tail light and meter lights, then pull the elect plug off the headlight switch and look into the plug for a burnt condition on one of the pins in that plug. If so, then you probably need a new headlight switch harness. Short harness of about a foot to foot and a half. Maybe a new switch to go with it.

Illumination fuse? If so , look at the White/Green wire in the corner of the elect plug for being BURNT.

It's the illumination fuse that is blowing. Where is the elect plug?
It's a 1986 turbo series 4 hardtop.
For some time i haven't been able to switch to high beam. The high beam dash light stays constantly illuminated at all times when the headlights are on and a relay near the front of the engine bay buzzes when i try flicking high beam on. Could that be related to whatever the problem is as well?

The headlight switch (actually Cluster Switch) is on the left side of the instrument cluster. The electrical plug for it is out of view and can only be accessed by pulling the instrument surround off.

The left cluster (headlight) switches have a history of interior faults, usually an open in the parking light circuit, but might also be the source of a short in the headlight circuit.

To track down the short you will have to trace the circuit from the main fuse through to the ground; break (disconnect) the circuit at each connector along the circuit until you find the one that eliminates the short. The short will be between there and the last one you disconnected.

You really need to get this sorted out before the short starts a fire under the dash.

I've seen complete wiring harnesses melt down because of this :icon_no2:

Pull the plug off. The White/Green is the power wire from the Illumination fuse.

Key is not needed to do the following.......Jumper the White/Green wire to the Red/Black wire. The side lights front and rear should light up. IF they do then the short is not there.

Then jumper the white/green to the Red/Green wire in the plug. The instrument lights should light up. If the fuse does not blow the problem does not lie there.

If the White/Green is burnt and the above items work, get another short harness and or switch. OR somewhere in the archeives there is a work around where you can install a relay to overcome the fault in the switch. An Icemark thread on installing a relay somewhere.