The Stovebolt Site Forums The Shop Area The Electrical Bay Dash gauge lights not working properly.

Hello Stovebolters,
The gauge lights are not working properly in our 1952 3100. I regularly must turn the headlight switch knob back and forth numerous times and rapidly to get the gauge lights to come on. A second problem is that the gauge lights are very dim and will not brighten even with turning the knob further. Our pickup has been changed over to 12 volts many years ago. Any suggestions greatly appreciated.
Chuck 52

Most likely the potentiometer that controls the dash lights is either worn or dirty. It would take a replacement headlight switch to fix it. You might be able to remove the switch and clean the coils on the potentiometer. Picture has an arrow pointing at the potentiomenter. Replacement switches available from Jim Carter. LINK

Cleaning the potentiometer will work. I use 0000 steel wool on the coils and 800 grit sand paper on the brass contact.

Chuck, I've never driven a car in my life where I thought I needed to dim the dash / instrument panel lights. I've always kept them turned all the way up to bright.

Ol' Roy's instrument panel lights also only worked intermittently (mostly never).

Rather than buy a new switch that is probably junk from China like most things today, I simply removed the switch, disconnected the instrument panel wire from its terminal, and installed it on the parking light/taillight terminal.

This way, the instrument panel lights come on full bright whenever the headlight switch is pulled out to one notch or two notches.

It works perfectly and I don't have to worry about treating it with kid gloves or hope the dash lights don't blink out.

The potentiometer on the switch in my ‘52 was broken in two. I was able to get a reproduction switch that matched and operated exactly like the original. It uses the original knob and shaft. Although pricy, it is an option.

Here is a link to LMC Truck that will give you some options.

Some time back I wrote instructions on how to revive/rebuild your headlight switch and make it like new again. Here is a link: https://tinyurl.com/y6f3lbgs

Hope it is helpful.

I`ve had great results using this spray lube/cleaner.
Working the switch L-R. I`ve yet to run into a light switch that could not be fixed.
That being said, what Otto suggested sounds like a good option. Would have saved me from accidently
leaving my dome light on.

Check your grounds as well.

Like Otto...

On the light switch, I moved the wire to the instrument lights from the rheostat to the taillight terminal. Instrument lights are on when the taillights are on; problem solved. Did the same with the parking lights.

So now when pulling my light switch out. First stop has parking lights, taillights and instrument lights. Second stop (pulled all the way out) adds headlights.

Almost, but not quite...First stop has parking lights, taillights and instrument lights. Second stop (pulled all the way out) adds headlights and turns off parking lights.

At least that is how it works on my '52 GMC.

I know what the factory default wiring is. I changed it to function as I stated.

Wow, Thanks to Kevin, Carl, Otto, Phak, Jon, Guitplayer, Rusty Rod, Gord and Fran and Bill.
Great suggestions - I will go down the list and give your suggestions a try. (soon as it warms up - 10 degrees here in Michigan as I write this.) With owning our '52 for over 30 years and being a stovebolter for most of those years your suggestions have been a great help many, many times in the past. Thanks again.
Chuck

That’s a classic worn headlight switch issue. The dimmer for the gauge lights is built into the switch, and over time it gets dirty or worn out. That’s why you have to spin the knob to make the lights come on, and why they stay dim.

You can try pulling the switch and spraying electrical contact cleaner into it, then rotate the knob back and forth a bunch of times. Sometimes that fixes it.

If not, the switch likely needs to be replaced. Also double check that you have 12 volt bulbs in the gauges and that the cluster has good grounds, since both can cause dim lights.

Hope this helps.

Yes, Mike.
Very helpful. Thank you.
Chuck