1980 240D center console illumination not working

There are no lights illuminating the instruments on my Dad's MB 240D, 1980 model year.
I would appreciate any advice, towards my plan to change two light bulbs
that illuminate the center console. I have a wiring diagram, and I realize that a potentiometer might be at fault. As the hazard lights work, it seems Fuse #1 must be OK. That fuse protects the light bulbs in question, also.
Is there a trick to getting at those two bulbs? Or do I have to remove the entire dash board to get at them? Even if I removed the under-dash obstructions, it seems these bulbs are too inaccessible from below, to replace them that way.
Is there some way to remove the clear screen that protects the instruments? If that were gone, it seems I could get to the two bulbs, which project light down upon the instruments.
Thanks for any help.
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realize
seems
the
instruments?
Are you talking about the instrument cluster lights or the A/C control lights ?
If you are talking about the Instrument cluster lights, you need to pry out the instrument cluster. You can do this by removing the kick plate below the dash and reaching up and pushing on the inside of the instrument cluster - it is just a push fit into the dash. You can also remove it n\by making some hooks out of stiff wire and inserting them on each side of the cluster. This link explains it:
http://www.mercedesshop.com/shopforum/showthread.php3?t2102&highlight=remove+cluster
BTW - You might want to go to that forum for help on diesels - good guys there.
Once you have pried the cluster out, you need to undo the oil pressure line and unscrew the speedo - There is also one big electrical plug to pull, then it will come right out. You will see the bulbs - check them out - they are probably burned out.
If its the A/C light, ask at www.Mercedesshop.com - My '85 may be different from the 240D. It required peeling off the wood trim around the controls and then unscrewing the face plate. There is just one bulb and a bunch of light tubes that run to each button.
good Luck
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If both lights aren't working, and the center console lights as well, then your rheostat (the dimmer) might be broke. It wears over time and if the contacts are dirty or if the resistance material has crumbled away, then everything is dark. You can replace the rheostat or just bridge the two poles on which it screwed on, giving you maximum light all the time.
The instrument cluster light bulbs are located at the top of the instrument cluster. Not easy to change without removing the instrument cluster.
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"If both lights aren't working, and the center console lights as well, then your rheostat (the dimmer) might be broke. It wears over time and if the contacts are dirty or if the resistance material has crumbled away, then everything is dark. You can replace the rheostat or just bridge the two poles on which it screwed on, giving you maximum light all the time. "
I rejuvenated mine when I had the instrument cluster out. I sprayed electronic contact cleaner into it while working it back and forth for about 5 mins. Pots tend to get dirty over time and develop bad spots. Many times, if you just work it back and forth without any cleaner you can find some spots where it will still work. Mine is working fine now. If you want to replace it, they are available, though I think they are like $60. As suggested, shorting it is another alternative.
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