The Stovebolt Site Forums The Shop Area The Electrical Bay Head Light Switch(?) issue

1953 3100 that has been converted to 12v

Everything on the head light switch was working great. Then suddenly, the parking lights at the first switch stop worked fine, but at the second switch pull, nothing works, even the instrument panel light goes out.

There is a metallic clicking sound every 5 seconds eminating from the switch box, so I thought is was a bad switch. After installing the new switch same clicking sound and same results.

No changes made to any other part of the truck/electrics.

Any help?

thanks...

Find the short circuit that's making the circuit breaker in the light switch open up and reset. Hint- - - -it's probably in or near the dimmer switch!
Jerry

If they hadn't built that circuit breaker into the switch the diagnosis would be much simpler, just follow the melted wiring!

1. Do the headlights come on for a few seconds and then go off in sync with the clicking sound?
2. Did you click the dimmer and retry switch?
3. How long ago was truck converted to 12V. Long before this happened?
4. Any wiring done recently? Any lights added or other accessories/components added, removed, replaced recently? (I know you said none, just rechecking). Any mechanical work that required electrical to be played with?
5. ALL bulbs including headlights changed to 12V?
6. Have you checked whatever fuses you have?
7. How many "PARKING" lights come on and stay on with first position, front and rear?
8. Any relays added? Relays click.
9. Headlights 12V sealed beam, non halogen or other than orig type?

Check your battery terminals/cables, especially ground at battery post and other end. Clean and renew to shinny.

Put your hand under dash and feel the switch as it "CLICKS" to be sure the noise is the switch itself. If it is the thermal breaker on the switch, it takes 42 Amps to trip it.


Take a good look at the inner fender headlight terminal blocks.

If all 9 questions are answered and you find nothing amiss visually, we may follow up a bit........ and then can proceed with electrical troubleshooting.

Or follow the fire. I agree with Jerry...look at the dimmer switch first. Something is grounding out somewhere and that's a good place to begin. Second place to look...a missing grommet on the inner fender where the headlight wires pass through. Years could have worn away the insulation and you could be going to ground right there. Good luck!

Resolved!

[Seinfeld Voice] Dimmer Switch!

Thanks all.

"I love it when a plan comes together" (Hannibal Hayes Voice) The dimmer switch lives in a very hostile environment with lots of rain, mud, and salt. It shorts out or open circuits often. GM sent a new invention to the MIT engineering school years ago for their comments, a dimmer switch mounted on the steering column. MIT replied that "All our faculty and most of our students are getting their feet hung up in the steering wheel while trying to dim the lights- - - - -put the switch back on the floor where the Lord intended it to be!"
LOL!
Jerry

Having worked with a couple of high IQ MIT grads in my professional life who didn't have enough sense to come in out of the rain, I can appreciate that Jerry.