Anyone know if the switches in my 87 TDT are individually lit or are the "backlit"? Some of mine are lit some are not. Cant figure that out (why some are not lit mean) The bulbs must be Tiny if that is the way they are. Second question, Can the bulbs be replaced or does the switch have to be replaced?

Depends on the switch. Most of them are fiber optic lit from a single lamp....a few are not (window switches, shifter, and hazard switch)

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Although not too recently, I did have my window switches out and cleaned all the contacts and internals. Unfortunately, I didn't take any pictures, but I distinctly remember very small bulbs in all of the switches. It didn't seem like they were removable.

If a bulb is burnt, it may be obvious once you have the switches out (you might be able to check with a multimeter, but, I'm not sure which pins do what). Just be careful when disassembling them - note which way they go, too, there are differences from left and right. The ball bearings and springs can disappear if you're not watching where they are. I took mine apart in a shoe box. Somewhat of a pain to put back together, but, just line everything up and push it together evenly.

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1982 240D, sold 9/17/2008
1987 300D TurboW124.133 - 603.960, 722.317 - Smoke Silver Metallic / Medium Red (702/177), acquired 8/15/2009
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Well all four window switches are out as well as the shifter light. Probably some other reason for that. The Switches however are not fed light from any other source. Probably never get it working again.

In the 1987 300D Turbo (W124, OM603, sedan and wagon), none of the switches are fiber-optic lit, they have tiny LEDs in them. The shift quadrant has a regular 12V lamp. Since the LEDs rarely fail, I recommend looking for a failed fuse, wire, connector or "Instrument illumination control unit" (N40, behind the instrument cluster). N40 controls most of the lights in the console; the purpose is to reduce the load on the rheostat. Given the lights you describe as "out," I suspect a wire or connector.

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Well Jeremy, I am going to give you 100% on this one. After you mentioned that I remembered that I had unplugged that modual under the dash as the interior lights would not go out. I got another from a donor car for the courtesy module but had inadvertently unplugged this one you are talking about. I pulled the cluster and plugged it in and bingo lights!