Dimmer switch wiring

[SeriesShorty]

After my rewiring job on the ole IIa that has now become a 12v truck, I am having just a few little wiring problems that I need to sort. My headlights aren't working properly. I have what I believe to be low beams, but I click the dimmer switch over the lights go out altogether.

I'm gonna start my troubleshooting at the dimmer switch. Does it matter which prong is for power in, low out and hi out?

I had wired it with the power in going to left vertical blade. Hi on the top horizontal blade, and low on the bottom horizontal blade.

Just want to confirm this is not the problem before moving down the harness to the relays controlling each.

Thanks,
Jen

[TeriAnn]

After my rewiring job on the ole IIa that has now become a 12v truck, I am having just a few little wiring problems that I need to sort. My headlights aren't working properly. I have what I believe to be low beams, but I click the dimmer switch over the lights go out altogether.



It is pretty common for the internal contacts of the switch to corrode over time. Since they are not built to be serviced the best thing is to replace it when either the high or low beam stops working.

I've stopped using the Lucas ones because of expense and have been using generic foot switches from my auto parts store. The mounting hole space is different so I needed to drill a new hole for mounting (reusing one of the old holes).

There are a few different contact arrangements. The easy way to see what you have is to pull the wires at the switch and ring the contacts out with an ohm meter out continuity light. The blue wire goes to the common connector and it doesn't matter which of the other two the blue/white and blue/red wires go.

[SeriesShorty]

Thanks TeriAnn, I hadn't even thought about just replacing the dimmer switch. It was working when I took it off the truck a year ago...but it's been a long, rough year being bounced around in a box so it's very possible that it is defective at this point.

Thanks for the suggestion!

[SeriesShorty]

Update: Big thumbs up for TeriAnn, you called it right on the money. A NAPA stop and $8 later I have low and high beams. :thumb-up:

You the man...well, you know what I mean! ;)

[TeriAnn]

Update: Big thumbs up for TeriAnn, you called it right on the money. A NAPA stop and $8 later I have low and high beams. :thumb-up:

You the man...well, you know what I mean! ;)

I think so but it is not the way to get followup help. You'll have to come up with a better way to say thanks to a woman.

[SeriesShorty]

I think so but it is not the way to get followup help. You'll have to come up with a better way to say thanks to a woman.

Coming from another woman, I'd figure you'd have a sense of humour about it. Sorry if I ruffled your feathers, that wasn't my intention. I'll just state simply...I appreciated your help.

[SafeAirOne]

A little late, but it sounds like your power wire was on the wrong terminal; When that happens, only one side (high or low beam) will illuminate. The other two wires don't matter which remaining terminals they're connected to,as TeriAnn said. There are only 3 terminals and incorrectly wiring them won't hurt anything, so you could find the correct power terminal through trial and error pretty quickly by changing the position of the power wire.