'73 Instrument Panel Lighting. Problem with dimming.

[George H.]

When I turn-on the headlights, the instrument panel lights come on but remain dim or go off completely when I rotate the headlight knob. The curtesy lights do come on when I turn the knob completely to the left, but, when I rotate the knob for up or down gauge lighting, all gauge bulbs remain dim or go off. Is that a good sign that the headlight switch rheostat, which controls the dimming, is bad? Switch is original and "50 years old" this year. How hard is it to replace the switch?

'73, LS4, M21, 953, Coupe

[Russ S.]

Re: '73 Instrument Panel Lighting. Problem with dimming.

Sounds like the switch to me. To replace you would need to lower the steering column at least a little and remove all screws holding the ash in. Pull the dash downward slightly and back which should give you enough room to get at the switch.

[Joe L.]

Re: '73 Instrument Panel Lighting. Problem with dimming.

Sounds like the switch to me. To replace you would need to lower the steering column at least a little and remove all screws holding the ash in. Pull the dash downward slightly and back which should give you enough room to get at the switch.

Russ and George-------


I agree; almost certainly the rheostat on the light switch which means the entire switch has to be replaced. If yours is a 50 year old original, it's led a charmed life because these switches usually don't last anywhere near that long.

[George H.]

Re: '73 Instrument Panel Lighting. Problem with dimming.

I appreciate the feedback. I can buy a replacement switch for $60 and that includes a new rod & knob. The fun part has not started, but, sounds like a lot of work. Might have a specialty shop do it. I'm sure that will mean a lot of $$$. As a side note, in the past 30 years, I don't believe I've driven the "mean machine" at night more than once or twice. Purchased the car as second owner in Dec.1979 from a co-worker. Have a good day.

[John S.]

Re: '73 Instrument Panel Lighting. Problem with dimming.

George, while I agree that it sounds like you need to replace your HL switch, I would also take some time to inspect and clean all of the grounds in the electrical system. Lighting systems can do strange things when the grounds are dirty/corroded especially on FG bodied cars. Good luck !!

[George H.]

Re: '73 Instrument Panel Lighting. Problem with dimming.

I was part of that team. Appreciate the feedback.

gator943
Ocala, FL

[Joe L.]

Re: '73 Instrument Panel Lighting. Problem with dimming.

I appreciate the feedback. I can buy a replacement switch for $60 and that includes a new rod & knob. The fun part has not started, but, sounds like a lot of work. Might have a specialty shop do it. I'm sure that will mean a lot of $$$. As a side note, in the past 30 years, I don't believe I've driven the "mean machine" at night more than once or twice. Purchased the car as second owner in Dec.1979 from a co-worker. Have a good day.

George------


Replacing the headlight switch is really not all that difficult. Many, many years ago I lived with a defective headlight switch on my original owner 1969 which had the same problem as yours. I did this because I feared the work to replace it. When I finally did it, it turned out to be not too difficult a job, at all.

When you get your switch out, I think you will find that the "paddle" of the rheostat is loose on the shaft. There's no way I know of to fix this so you need to replace the switch,

[George H.]

Re: '73 Instrument Panel Lighting. Problem with dimming.

Appreciate the feedback. Switch is on order.

George