W123 240D dash lights issue

[sceh]

The dash lights on my 1981 240TD have suddenly stopped working. The lights on the auto gearbox shift work but the other lights andd switches don't. Fuses are all OK.
Is this the dreaded rheostat or something else? Does the rheostat control all these lights?

thanks for any pointers before I strip out the dash..

 

[Ted]

Have you tried rotating the dimmer (trip reset button) a few times?

 

[sceh]

Yes. No dice so far

 

[sceh]

In fact, in spite of having the car from new, I never even knew there was a dimmer so it has never been moved I suspect

 

[Ted]

I would by by pass the dimmer by soldering a piece of wire across it.
The dash lights on the w123 aren’t very bright anyway.
You may find it is a dry joint where the dimmer is soldered to the pcb.