On my 89 740 my orange overdrive light glows dimly occasionally. The overdrive button works fine and I have no problems shifting in and out, it's just that it likes to glow sometimes. What might it be?

I don't know if this could be related or not, but both of my turn signal lights used to dimly glow. It turned out that I had a bad ground. Once that was fixed, the glow disappeared.
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Regards,
Eric Staufer,
'89 244DL 117k (now with a fixed odometer!) :-)

I have a similar problem in my 1990 240. The light that indicates a light is out on the dash is always lit when my headlights are on. I have checked and all light are working. Then sometimes it decides to flicker for a few minuites, and may stay off for a bit. Then when I am rolling the windows up or down it stays off until I am done. I am clueless, any help is greatly appreciated!

I do have the "light out" warning light which is constantly on no matter what I do though I've checked all lights and none seem to be out.

Try to dis-assemble the speedo and check if any of the light on top have fallen down. They might be glowing through a missing bulb?