Gremlins?

[doctor4766]

I recently noticed that there is no longer a tach in my tic toc tach even though it was working when I acquired the car a couple of years ago.
I was a little miffed but wasn't gonna get too upset about it for now.
Even more recently, I noticed that there is no longer any dashboard illumination with the head lights on, even if I roll the dimmer switch back and forth to find that "happy" place on the dial.
And now just today when I thought I'd fiddle with said dimmer switch, I realise that the interior light will not turn on using the same switch.
Is it likely that there's a connection here?
All gauges are otherwise operating like normal ie temp, oil and fuel, so I'm assuming the voltage regulator in the dash is ok.

[Nacho-RT74]

What about pilot lights? High beam indicator, turnings.

Sounds like a missed ground. Althought voltage limiter gets also ground, at least on 3rd gens cluster with PCB, ground is wired straight to PCB and VL gets it from there, but missing chassis ground could cause the rest.

[Nacho-RT74]

Checking 2nd gens diagrams and no, they don't get a wired ground at PCB like standard cluster on 3rd gens get, so all the cluster gets just chassis ground on 2nd gens. Unless a weak chassis ground could keep quite alive the VL but maybe not the rest.

Dimmer wheel is also feed with chassis ground from cluster to turn on the dome light.