I have a 1955 chevy 3200 second series and am having a bit of lighting problem. When pulling the knob to turn the headlamps on, it works great. No isssues when normal headlamps are on. When I push the dimmer switch on the floor to turn the high beams on, it may take several minutes up to 20 and then the headlights turn off completely. The lights inside the truck still are on no problems. As soon as I press the dimmer switch again the normal lamps turn back on and nothing is wrong. It seems that something shorts when the high beams are on. I have been told that possibly it is the headlight switch or the dimmer switch that is bad. Is there a way to test each to see which it truly is so I know which to replace??
i have taken those switches apart and cleaned the contacts. they are pretty simple, when you step down it rotates the terminals.
If you have a test light or volt meter with the headlight switch on and the connector unpluged one wire will have voltage so then plug it in and you should have two wires with voltage then if you push the dimmer switch there should be a change it the voltage from one wire to the other ie low beam and high beam If you loose all voltage it has to be a problem with the light switch or the wiring from it to the dimmer switch if you still have voltage at the one wire then its a problem with the dimmer.
Not likely the headlight switch. I think '55 headlight switches have built in circuit breakers. When the high beam switch removes the low beams from the circuit and adds the hi-beams, it causes an overload (i.e., short) and trips the breaker in the headlight switch. This is why headlight go out and other lights stay on. So, something is wrong in the hi-beam circuit. It could be a faulty hi-beam switch as suggested or it could be a short in the wiring from the hi-beam switch to the headlights.
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