Mechanics

MODELS HEAD LIGHTS

1970 GMC Other

Electrical problem
1970 Other GMC Models V8 Two Wheel Drive Manual

Why do the headlights in my 1970 GMC truck keep turning on and off even after installing a new switch?
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Jayphus
January 17, 2010.



It does that becaue teh circut breaker is kicking the off an don so you don't burn your truck up. Disconnect the dimmer switch onthe floor and turn headlights on and see if stops. If it doesn't then you have a wire touching ground someplace, in otherwords shorting out. If it does stop it by disconnecting the dimmer switch, then replace the switch, it's on the floor. They get water and corrode causing that alot of times.

Hmac300
Jan 17, 2010.