Climate control and shifer lights not working - PeachParts Mercedes-Benz Forum

jbach36 · #1 11-19-2011, 11:36 PM

Suddenly the shifter and climate control lights aren't working.

I'm going to check my fuses now, but I doubt they have a single fuse that handles a few little light bulbs.

Any other ideas?

jeff 1991 300d, 166k

kerry · #2 11-20-2011, 10:24 AM

Noticed the same thing on my daughter's 84SD when I drove it last night. I'm curious as to the responses.

compress ignite · #3 11-20-2011, 04:05 PM

The Shifter illumination is a single bulb accessible,after you remove the Wood.
('Not Too Bad to do,Careful of that Wooden Shifter Console Cover!)

The CCU illumination bulb(s) require removal of the CCU unit from the Upper Console..
('Not had to attempt that particular Joy,Yet)

The Most Fun in replacing W124 Illumination is the Teenie,Tiny Little bulb inside
the Passenger Side Rear View Mirror Control in the Console.It's Soldered in!
(The Bulb's about the same size as pencil lead.)

mccauleybil · #4 11-20-2011, 07:00 PM

I replaced my ccu yesterday, and began looking for the shifter light assembly. My 1982 300sd ccu lights and window switch lights lite. My shifter light is dark? Any help out there?

Dave Donaldson · #5 11-20-2011, 07:18 PM

87 300SDL The prince of Darknes has struck my shifter , window switch, and front dome light,, not just your regular bulbs I'm guessing, Any chance these are just normal type bulbs available at Joe's garage ? And the heater will not turn off ,,, ok for now up here in Canada but the fan motor goes on and off when ever it feels like it,,,haunted me thinks,, Got her in June and not to mislead anyone that I am lazy I have done the rotors exhaust, master cylinder, belt w/ tensioner and idler, hoses fuel and vacuum,alda, whole new front end $$$$$,,all filters, and fluids, . Just received a timing chain, but will have to wait until spring,, working outside,, on the to do list is frt seal / crank shaft,, and perhaps test the injectors and ip timing,, but will spend some time reading all the posts here before I wreck something expensive :} any advice will be gratefully appreciated..Cheers ! ps added a vid on u tube of cold start up I think she sounds ok but not too noisy ?
Mercedes Benz 300 SDL start up - YouTube

shadetree77 · #6 11-20-2011, 07:56 PM

the shifter light on the SD is illuminated via fiber optic cable from the "octopuss" housing behind the CCU. the "octopuss" contains a single bulb which lights all the buttons (antenna, rear dome light, defrost, etc {not the hazard, it has its own bulb}) above the CCU as well as the shifter light...do the switches above the CCU light up? if not then the bulb inside the octopuss is burned out

kerry · #7 11-20-2011, 08:14 PM

How does a person access the octopussy?

tbomachines · #8 11-20-2011, 08:34 PM

Quote:

Originally Posted by kerry

How does a person access the octopussy?

Take out the CCU, and remove wood if you can't get your hand through the slot. Its more by feel than anything else - its mounted back against the firewall. You can follow the wire from the CCU bulbs back to the "octopussy" as Bond, Kerry Bond calls it above. Here's what I wrote in my blog after a bloody-knuckled and extremely frustrating attempt at reconnecting the octopus/spider:

Quote:

All of the switches on the top of the console except for hazard lights --rear reading lights, defrost, sunroof, and antenna (may be more depending on options) are lit by means of fiber optic cables in back of the dash. There is one light strand, much like a christmas tree wire, powering all the climate control and switch lights. I believe these are wired in series so if one bulb goes out, the following will also go out. There are 4 bulbs located in the climate control unit (I will get to that in a second) and one bulb reaches back into the firewall to a cluster commonly called either and octopus or a spider. The fiber optic wires coming off of it go to each of the top switches, and one goes down into the shifter console to light the PRNDSL selection. Conveniently, my octopus was completely torn apart by the previous owner who pretty much scrapped the whole interior. After many hours of toiling I recommend just forgetting about it, you won't easily get those fiber optic cables back into the octopus--it is so far back against the firewall, it gives almost no room to work, especially for a precise placement of these wires.
Back to the light strand. The first two bulbs on the strand light the left side of the climate control--the wheel and left couple buttons. Then, the strand reaches back to the firewall where ONE bulb (stock bulbs are pretty dim) lights all of the switches and center console, then the next two bulbs return to the climate control to light the right flap buttons and fan speed/auto buttons. Since I gave up on the octopus, none of my switches light up except for the hazard lights, and I replaced my climate control bulbs with LEDs to compliment the blue feel of the car.

I BELIEVE they are in series after my own experimentation, so the first bulb in the strand may be out...replace that and see if the rest turn on. I ended up replacing all of them with LEDs, which actually looks pretty good. Also be REALLY careful remoing the bulbs from the CCU slots, as that plastic is extremely brittle with age. I broke every single one of those sockets because I did not remove the CCU first, and assumed that they just popped out

Edit: above info is for the w126 and those who inquired about that. I imagine the W124 would be similar, if not identical.

MBeige · #9 11-20-2011, 08:36 PM

On the W124 I believe it's a "rice grain" bulb 2721 code (1.2W)

I just replaced the same shift gate bulb on my mother's 90 300TE.

The climate control pushbutton unit uses two of these, behind the silver tape. Getting 2 pairs should give you enough for the shift gate and climate control but since they're cheap enough might as well get some spares if you find more busted ones.

compu_85 · #10 11-20-2011, 08:45 PM

I'd replace them all while you are in there. 1.2w is the correct lamp, the 3w version will melt the plastic.

-J