anybody know what the deal is with the dash lights in a 240d?

It's the dimmer rheostat. Pull the dash (easy) and there;s a good chance you can *repair* the rheostat. Or buy a new one, or just jumper it so it's always full on.

Here's how:

I rejuvenated the one in my 300SD by removing it, spraying it full of electrical contact cleaner, and working it back and forth many times. Good as new now. Instead of removing the instrument cluster, sometimes you can move them around till you find a spot that works and leave it alone. If you need a new one, they are available, though pricey, ~$65

I wiggled mine for years and it worked. When I finally took it out the only problem was one end of the spring and come off. I putit back, dabbed a bif of JB weld to keep it in place and it worked fine.

Of course that was AFTER I'd bought a new one. I'd never heard of anybody fixing one before. But, uh, I'm not sure anybody had tried.

I cleaned mine (a '72) with alcohol and a q-tip about ten years ago, and haven't had a problem with it since. Mine just had a bunch of cermaic dust piled up in the coil that was blocking its function. Never heard of one having the end pop off. Glad that you were able to fix it.

Me too :-)

See for yourself though:

I wiggled it for years to make it work, but eventually it could not be made to work any more. It was a really easy fix, should have done it long ago. It's much much brighter now of course.