Headlamps Flash On and Off While Driving

[Raul]

I've had this issue before on a 1969 Dart 340 Swinger. Where the headlamps would not stay on. They just randomly flash on and off during the course of driving at night. Now on my 1968 Barracuda I'm encountering the same thing. What would cause this? Is it a short somewhere? If so, Where? Has anyone else encountered this before? Maybe I need a new headlamp switch?How do I even begin to investigate this without going into an expensive automotive electrical shop?

 

[halifaxhops]

Check all of the headlight grounds to start with, sounds like a ground issue if it is only the headlights.

 

[CUDA69]

A bad headlight switch will do that.

 

[jimjimjimmy]

grounds or switch . my problem was the switch .

 

[Moparman1806]

I had a bad dimmer switch do that

 

[Plymouth Pete]

I had a bad dimmer switch do that

This was one of the reasons I replaced my headlight switch connector. It was making intermittent contact with B1 main power on the switch. Here is how.
Melted Headlight Connector Replacement Found

 

[slantsixdan]

Could be a bad headlamp switch, a bad high/low beam kickswitch, a faulty connection at either of those switches (replacement switch connector in good quality see here) or elsewhere in the circuit, a flaky ground, or — if the lights only start blinking out after they've been operating at least a minute or two, it's likely an electrical overload tripping the thermal cutout breaker built into the headlamp switch, either because the cutout has grown "soft" or because of increased resistance in the circuit and/or higher-than-stock headlamp wattage. See here to understand the good fix; CrackedBack (here on the board) sells good ready-to-install harnesses.

 

[Raul]

Thanks to all your replies....I will change out my switch and go from there.

 

[jos51700]

Motorcyclists pay extra for that ****

 

[rustycowll69]

Thanks to all your replies....I will change out my switch and go from there.

it's been my experience, that either more current draw by higher wattage replacement headlight bulbs, or too much resIstance in circuit due to poor and/or corroded connections, or any combination of the above reasons, can cause the headlight switch to overheat, and trip its internal circuit breaker.

 

[Pawned]

I when I rewired mine, I added at least 10 additional grounds to the wiring.