I have been driving around fine for quite a few months and now randomly I am popping headlight fuses and I have not changed or altered anything. I can ride with parking lights on all day and the fuse does not pop. Both headlights illuminate. Could a headlight go bad and still work causing the short? I have the old school push/pull light switch, nothing fancy, could that short out and be the issue? Has anyone seen anything like this before? Thanks in advance.
Might have a chaffed wire,somewhere. Unplug the left light try it. Then unplug the right try it. Could be in the insides of the light housing. Could be going to the dimmer switch. Try high beam see if it still blows. Lots of places to look. My guess in the grill to headlight area. Only my opinion and it was free.
Blowing a fuse means that the light or circuit is drawing more power (amps) than the fuse can handle. I'd follow what 325W suggested and that should tell you what side the problems on. As it doesn't see to happen all the time I'd say that he may have hit it in that there is a wire that some times makes contact with bare metal shorting out the circuit and blowing the fuse. On my OT rig (71GMC) I had a hell of a time burning up dimmer switches and the head light switch after I changed to H-4 Halogen lights as they drew way more amps than the old stock lights or the off the shelf at the parts house Halogens. I ended up putting in relays to cut down on the load though the switches and that ended the problem.
Sometimes as simple as license plate light shorting Sent from my SM-G900V using The H.A.M.B. mobile app
Have you changed anything as far as to the type of lights on the car? I have an original 32 Ford, with a replacement wiring harness (high quality). When I went to higher amp halogen bulbs (35 Watts), then this put me right on the edge of what the fuse could handle . . . so I had to increase the Amps of the fuse itself. I've seen cases when there is an intermittent short, intermittent ground or where the fuse is right at Amp draw capacity . . . so when it gets hot, it tends to blow.
Where is the fuse located? I had a switch with the fuse mounted on it..the rivet holding the fuse mounting clip was loose causing bad connection and heating up melting the fuse..
Fuses should NEVER be used in a headlight circuit. If you need overcurrent protection, use self resetting circuit breakers!
Remember all that power goes through the dimmer switch first ,the offshore ****ty ones don't last long without a relay ,,, they get hot and burn inside and then go to ground !!!!!
That's my thoughts, too. Lost low beams one night, it was the dimmer switch melted inside. Only the current for the headlights go through it most of the time. Most people wire the tailights and park lights on a different circuit so you don't lose them if you lose the headlights or vice versa.
Too old to drive at night . Don't have headlight problems. Bad connection, loose connection, poor ground, cheap switch, bad dimmer switch, short to ground, short to voltage. A few things to check. Had an old scout that would get moisture in the dimmer switch and kill the headlights.
Thanks for all the suggestions, I'll post the fix when I figure it out. Sent from my SAMSUNG-SM-G925A using The H.A.M.B. mobile app
I'm with the "no fuse" crowd. The closest to a fuse that I've seen is a "fusible link" (basically a meltable wire) to power headlights. I guess whoever wired your car may have set it up that way, but maybe both the wires and the fuses are undersized for the headlights. I'm not a big fan of adding relays to older cars, but maybe this is a good case for a headlight relay.
I had a similar problem with my old black mordor Deuce about 10 years ago and after multiple blown fuses and chasing gremlins for a few months I ended up replacing my headlight switch and never had another problem. HRP
I'm funny about switches on old cars, if I know nothing about how old they are, I chuck them and get new ones. Real cheap insurance. Dimmer switches can wreak all sorts of havoc.
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