Headlights go on and off

[MikeB]

Yes, the light switch's internal protection may be tripping/resetting, depending on how much current your lights are drawing. Standard sealed beam headlight wattage is 60/55 watts. H4-type halogen bulbs can be 60/55, 100/80, or even 130/90. The second two can even melt wire insulation and connector sockets. Also, what do you mean by "driving lights"?

The problem could also be a wire that's touching ground intermittently. In any case, it sounds like the column mounted switch or wiring has some serious problems.

As for the alternator, it's just fine if the battery voltage measures 14.4 volts with the engine running. Any more than that (say 15-16) means a bad regulator, which can burn out bulbs, fan motors, etc.

 

[Andreas Wickman]

My Silverado 83 had exactly this. It was the thermal fuse in the headlight switch. A rely in the hi beam circuit fixed the problem.

 

[Dan Brown]

The circuit breaker for the headlights is on the switch. Maybe it's worn out which may be why the headlights go off and on. I'd try a new headlight switch, or at least check the one that's on it.

 

[gmbellew]

The circuit breaker for the headlights is on the switch. Maybe it's worn out which may be why the headlights go off and on. I'd try a new headlight switch, or at least check the one that's on it.

a way to test that would be to unplug 1 light and reduce load and see if the light stays on. if so, adding relays to reduce load or replacing the switch would be the solution...or both

 

[Radiohead]

Yes, the light switch's internal protection may be tripping/resetting, depending on how much current your lights are drawing. Standard sealed beam headlight wattage is 60/55 watts. H4-type halogen bulbs can be 60/55, 100/80, or even 130/90. The second two can even melt wire insulation and connector sockets. Also, what do you mean by "driving lights"?

The problem could also be a wire that's touching ground intermittently. In any case, it sounds like the column mounted switch or wiring has some serious problems.

As for the alternator, it's just fine if the battery voltage measures 14.4 volts with the engine running. Any more than that (say 15-16) means a bad regulator, which can burn out bulbs, fan motors, etc.

Don't forget boiling off the battery electrolyte

 

[82sbshortbed]

Yes, the light switch's internal protection may be tripping/resetting, depending on how much current your lights are drawing. Standard sealed beam headlight wattage is 60/55 watts. H4-type halogen bulbs can be 60/55, 100/80, or even 130/90. The second two can even melt wire insulation and connector sockets. Also, what do you mean by "driving lights"?

The problem could also be a wire that's touching ground intermittently. In any case, it sounds like the column mounted switch or wiring has some serious problems.

As for the alternator, it's just fine if the battery voltage measures 14.4 volts with the engine running. Any more than that (say 15-16) means a bad regulator, which can burn out bulbs, fan motors, etc.

Driving lights or parking lights or running lights. There's different ways to say it. That's what I meant.

 

[82sbshortbed]

Went ahead and got new switch and pigtail coming Saturday. Hope this does the trick.

ACDelco GM Original Equipment D1588 Headlamp Switch https://a.co/d/0pXK8jm

Standard Motor Products HP4520 handypack Headlight Switch Connector https://a.co/d/7aiH8zz

I feel that yall are right about it being the switch.

 

[Grit dog]

You know the trick to removing the headlight switch, correct?
Not a trick but there’s a spring loaded release on the backside of the switch to release the knob

 

[82sbshortbed]

Didn't know that so thanks for the heads up @Grit dog