Just bought a 72 GS 455 ragtop and need to find out why my high beams only work. I changed out the switch in the dash (royal PITA) and it did nothing. By chance if there are only high beam lights in all 4 of the sockets, would that cause an issue (Haven't checked that yet) Also, are the inner lights the high beam or the outer?
All 4 actually have high beams . The outer are low beams AND High beams . The inner ones are High beam only . The outers have 3 prongs on the bulb and the inners have 2 prongs on the bulb . Most common cause of problems is the dimmer switch itself . It has 3 wires to it . One is from the headlight switch and then depending what position the switch is in power goes to the Low beams ( one wire ) OR the high beams ( other wire ) . Easy to check with a test light . First make sure , like you said , that the bulbs are correct . And they are working .
I gotta check the bulbs. Like I said, All 4 light up and after putting in new switch, all 4 still light up. I mean there is no floor switch or any other switch other than the dash switch I replaced, correct? Believe it or not, I had a nightmare with the flashers all going on whenever the left turn signal was turned on. I replaced the switch and relays and it did the same thing. I checked the bulbs and the previous owner had 2 way bulbs in the back up lights. I put the correct bulbs in and all those other issues went away. The 2 way must have been shorting out the lighting.
Dimmer switch is on the floor . to the left of the brake pedal . pushing it changes Low to High beams
That could be the problem, there is no dimmer switch on the floor, like my GTO had. Thought is was a Buick thing and was in pull switch. The previous owner must have really did some handiwork. Thanks for clarifying that.
Funny what people Butcher . Look around that area . Could be he shoved it somewhere . Or you'll see the plug for it he jumped out . Looks like a pyramid . 2 on the bottom and 1 on the top
If your dimmer is missing, you’ll be better off with a used original USA one than a new one. Even the AC Delco part is a chinesium replacement now. Patrick