1981 300D Dashboard Lights On & Off
 

Guys, the lights on the instrument cluster are tied to the lights on the rest of the dash, correct? Backlight for the temperature controls, etc?

80% of the time the lights are all dead. But every couple of weeks they all decide to light back up for a day or two and then die again. What a tease.

Is it possible that a potentiometer malfunction can cause this on/off problem? I never get a flicker. It's either on for a couple days, or off for weeks. Couple of times it seemed to happen on rainy days, but maybe that's a coincidence.

Any chance there's a loose ground wire causing it? I've removed the cluster; it's clean and all connections look solid, etc.

ZC

Usually it's the potentiometer as you suggest.

Do a search for rheostat. It's in the cluster. There's an excellent DIY for cleaning it, or there's a jumper option for bypassing it.

And yes, your original statement about the cluster lights and the console and temp control lights is correct. There's a bulb behind the console and fiber optic cables from the bulb to the switches.