I have a 1983 MB 300D with a few electrical issues:

the clock doesn't work
the rear defrost doesn't work
the lights on the center console don't work
the radio turns on but no sound
the seat belt alarm does sound

I've replaced the center console light bulb - its still doesn't work
An auto glass shop tested the rear defrost - it works but not via the switch
I've verified the radio wiring and connections - the speakers work

Is there some commonality here that could be causing all or most of these issues?

TIA,

JWJ

Did it happen before or after you replaced the center console bulb(s)? I dont remember offhand where the ground is for all that, but start with the ground points (most of what you list is grouped together); the speakers are normally the front/rear fader then it gets unplugged, or a defective fader switch (don't remember what year the fader started, so can't tell you if it's on that particular model)

__________________
Don't ask me, I'm a shop-owner by default

It was happening before the replacement of the bulb or anything else.

I'll look for the common ground. Any idea where it is?

And I'll check out the fader switch. You're speaking of the switch on the center wood console by the window switches, right?

Thanks again,

JWJ