Headlights

[lexdownunder]

I'm having trouble with headlights cutting in & out. I rarely drive at night but coming home from a car show last weekend, after about 15 minutes of driving with the headlights on, they would cut out for about 5 seconds then come on again for a few seconds then out again. It's only the headlights. Tail, stop & dash lights are perfect. I was only on low beam too. This happened last year & I replaced the dip switch which I was told may have been the problem.
Am I right that there is a bi-metal strip in the headlight switch that will heat up & act like the "make & break" in an indicator flasher unit???
Would a new headlight switch fix the problem or is there something else I can check first???

Thanks Guys
Lex

[simplyconnected]

Do you hear a 'clicking' sound when this happens? My instincts tell me you have a circuit breaker that is overloaded.

Follow your ears and locate the sound. Then unplug one headlight and see if the power still cycles. If so, you may have a short somewhere, causing excessive current draw.

The Technical Resource Library has electrical drawings showing color-coded wires. Every device plugs-in and so do wire harnesses. You can trace from the headlights back, or from the headlight switch forward.

We had a member whose breaker was cycling because of rusty license plate light sockets causing a short. I'm not suggesting this is your problem but when you find the cause, it will be an. 'a-ha' moment.

Troubleshoot your headlight circuit. It is very simple, starting at the headlight switch, then to the floor dimmer switch, through the firewall, and finally to your headlight lamps. Look for rust on the floor switch, and loose connections.

Do not forget your grounds. They are equally as important as your feed wires, but they use a terrible conductor (your car's steel body). - Dave

[scumdog]

It will most likely be a tired bi-metallic strip in the light switch.

I fixed it by fitting a double relay so the power circuit that use to go to the main/dip headlights was just used to 'trigger' the relay, separate power supply direct from the starter solenoid/relay to the lighing relay...and hence to the headlights.

No problems since and brighter lights.

[lexdownunder]

Headlights

Thanks Dave & Scumdog.
Dave, I haven't noticed any "clicking" sounds so I'm thinking there is no relay/circuit breaker but will check it out tomorrow. My "gut feeling" is that there is overload on the bi-metallic strip in the switch & that a relay will rectify the problem.
Thanks again guys. You two have given me plenty to check out.

Take care & have a great weekend.
Lex

[jopizz]

If you look at the wiring diagram you'll notice there's a 12 amp circuit breaker that comes off the dimmer switch. This may be your problem or it may be the dimmer switch itself. The circuit breaker is in the dash on the drivers side near the ignition switch. Mine is held in place by two screws that hold the top switch. I'm not sure what holds it in place on a hardtop.

[simplyconnected]

jopizz is the winner of this one. '58's and '59's both have circuit breakers. One is before the dimmer switch and the other is after. I knew the headlight switch doesn't have one, but I forgot about the remote breakers.

Adding a relay under the hood (for future, high-amp sealed beams) is a good thing but for now, find out why the 12-amp circuit breaker is tripping. They are inexpensive to replace. - Dave

[lexdownunder]

Headlights

Thanks fellas. You guys are awesome!!!!!
Will let you know what the outcome is when I get it sorted.

Cheers
Lex