Nothing is illuminated on the climate control unit. Are there bulbs to replace? Also the center and right vent are dark.

LOOK BEHIND THOSE 2 SIVER SQUARE TAPES

There is a bulb behind each of those silver pieces of tape. I believe they are 194 style bulbs. A small piece of rubber hose can be used to slip over the bulb to help remove it from the socket. To replace the vent lights you will need to remove them to gain access to the bulb. Here is a writeup on how to get to them out. The information is about halfway down the page on the link below.

http://w124-zone.com/downloads/MB%20CD/W124/Index/MiscRef.htm#anchor4082673

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1989 300CE

I remember my dealership telling me that my W124's ACC control unit's bulbs couldn't be replaced, and I'd have to purchase an entire new unit at some extortionate cost .

But to echo what everyone else has said: behind the silver tape squares.

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Steven Harrison

1993 300E2.8 - 196K
2001 E320 4MATIC - 86K

OK I replaced the bulbs in the climate control. Same bulbs as in the gearshift so I'm glad I got a pack of 10 for $5 at a parts store. The bulbs in the vents I'm only finding at the dealer for nearly $3 each. Anybody have a part number for Osram or Sylvania that matches the Mercedes number 000000-001061?

With a little digging I found these grey base bulbs are made by Spahn in Germany with part number 6924. No contact in the USA.

Did find them on Ebay Switzerland 10 Stück Spahn Glühlampen 12V 0.5W | eBay