1971 Monaco, dash light issue

[Sideburn Daddy]

Changed a new (NOS) dimmer, because the old one didn't work properly. Neither this new one. Instrument lights come on only when the dimmer is turned to its most upper position. It doesn't adjust the lights but instead it works On-Off-method. Another weird thing is, that the dash lights come on only with parking lights. When switched to main lights, dash lights drop off. Any good suggestions or wisdom.

 

[Cags70PolaraConvert]

Waiting for your answers, I have a similar issue. shouldn't the dome light go on when rolled all the way up?

 

[sprice]

Sounds like a dirty resistor in which you fix with a contact cleaner and turning the dimmer switch back and forth to get a better contact and/or a bad ground.

 

[HWYCRZR]

As said above, clean the contacts. Also member @Devinism can rebuild most of these switches.
I had a similar issue on my ‘68, it was pretty erratic. I tried to clean it but still had a couple of dead spots. I sent it to him and he rebuilt it. Works like new.

 

[Devinism]

Changed a new (NOS) dimmer, because the old one didn't work properly. Neither this new one. Instrument lights come on only when the dimmer is turned to its most upper position. It doesn't adjust the lights but instead it works On-Off-method. Another weird thing is, that the dash lights come on only with parking lights. When switched to main lights, dash lights drop off. Any good suggestions or wisdom.

I would take a GOOD look at your dash wiring. Remove anything that is not factory. Look for repairs, splices, places that have electrical tape. It sounds like some wires are crossed, or inserted in either the headlight switch, or dimmer switch plug ends incorrectly?