... found a bunch about the 123 on search but not the 124 ... the left half of the five switches across the bottom of the CCU are out, as well as the turnwheel for temp setting. Right half is nice and bright. Is there any chance I've got one bulb out, or is something else wrong? The whole left half went out at once ... and this conincided with me tampering around behind the unit with a boost pressure line, so I'm a little worried I may have knocked something off-kilter. I'm hoping it's just a bulb-out coincidence. What is the bulb distribution to the CCU?

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

Hi Bodi,
I'd guess a burned out bulb. It's been a while since I did mine, but IIRC there are two bulbs, and some clear plastic "light guides" which direct the light here and there. Not a difficult fix to put in a new bulb, might as well replace both while you're in there, IMHO.

Rgds,
Chris W.
'95 E300D

Thanks Chris ... I got he two bulbs ... now I just have to figure out how to get the old bulbs out of their little "hideaways." Guess I'll have to find some heatshrink tube, although it might just slide off and not pull the bulb out ...

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

Follow-up just in case anyone else wants a quick answer for this job:
There are two bulbs (burnout was indeed the cause of my loss of light), each behind a little square piece of metal tape. Each 12V 1.2W. They provide light for the temp knob, all five setting buttons, and all three fan speed buttons, even though it looks like they're just floating in the middle of nowhere. I got them out with plastic straws and super glue (such advanced tools, I know ...). I got the new ones in by using a straw as a "guide" to get it in position, and then pushing the flat head of a nail gently down the straw to push the bulb into place. Like loading a musket, only you don't get to shoot anyone afterward. So that's that, if anyone else is wondering.

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)