replaced octopus bulb, still no shift light - PeachParts Mercedes-Benz Forum

angst · #1 02-20-2007, 07:07 PM

84 300sd
Man this job is kicking my tail.
I started off pulling my panel for my window switches. So far so good. Interior of switch for problem window was really grimey. Contacts cleaned and I assume its good to go.
Next thing you know I read up on the fiber optic cables and the bulb in the octopus thingie. I brag to the wife about the cool german engineering with only one bulb to burn out or replace for all these components confident that I will have a well lit front panel in short order. Over 3 hours later after wrestling out the climate control and removing factory wire ties to get to the bulb way in the back I was spent. I denouced all enthusiam for german engineering and called it a night.
Start back to the project tonight. Bulb goes in, fibers light up, but no light at the shifter.
I can see only one cable sheathing going to the black shifter box. It goes into the front. There is no bulb access on the left side as Ive read some people have. Ive tried unbolting the 4 bolts that hold the black box down but there is vent piping on both sides that wont let me get to the bolts.
My window switches are lit by LED's and not fiber optic cuz I had all those apart. Any idea about my shifter light? Ive got this much time invested I dont want to do a 90% job.

Also. Ive gotta stop reading old threads or Ill never button this thing up. I read that there is a light in the center of the headlight switch and that you simply pull out. My knob pulls out about 1 inch and seems to be purposely spring loaded. Is this serving some control function I don't know about?

winmutt · #2 02-20-2007, 07:49 PM

In the W123 the shifter bulb is, amazingly enough, in the shifter. I can't imagine SD would be any different.

angst · #3 02-20-2007, 08:18 PM

My left side does have 2 black covers that you can pop out. One near the P and one near the 1. They sound similar to what those with bulbs have but there are no bulbs attached to mine.
The tabs are about 1/2in by 1in black squares and there is a long tab on them. they say part number 1262670440 on them. looking into the holes there is no signs of a bulb or wires anywere.

Eskimo · #4 02-20-2007, 08:45 PM

Quote:

Originally Posted by angst

Also. Ive gotta stop reading old threads or Ill never button this thing up. I read that there is a light in the center of the headlight switch and that you simply pull out. My knob pulls out about 1 inch and seems to be purposely spring loaded. Is this serving some control function I don't know about?

The threads I've read about the bulb in the headlight switch claimed that, at least for the W123 chassis, it's to indicate when the rear fog light is turned on - a rear fog light that isn't present on cars built for U.S. consumption.

#5 02-20-2007, 08:54 PM

Quote:

Originally Posted by eskimo

The threads I've read about the bulb in the headlight switch claimed that, at least for the W123 chassis, it's to indicate when the rear fog light is turned on - a rear fog light that isn't present on cars built for U.S. consumption.

That's correct, pulling the switch out one click turns on the fog lights (with low beams on). Pulling the switch to the second click would turn on the rear fog light (and the switch indicator light). On U.S. cars (without rear fog lights) the indicator light does not do anything.

thorsen · #6 02-20-2007, 09:04 PM

Quote:

Originally Posted by angst

84 300sd

Start back to the project tonight. Bulb goes in, fibers light up, but no light at the shifter.
I can see only one cable sheathing going to the black shifter box. It goes into the front. There is no bulb access on the left side as Ive read some people have. Ive tried unbolting the 4 bolts that hold the black box down but there is vent piping on both sides that wont let me get to the bolts.
My window switches are lit by LED's and not fiber optic cuz I had all those apart. Any idea about my shifter light? Ive got this much time invested I dont want to do a 90% job.

The black sheathed cable to the shifter box is a fiber optic cable. I had the same problem you did and just decided to pull it, thinking a light bulb would be on the end. I ended up pulling the entire fiber optic cable out of the housing. Not a good deal.

If it turns out that your fiber optic cable is dead (and it sounds like it might be since the rest of the lights on the octopus are ok) then your options are limited.

Jeremy5848 · #7 02-20-2007, 09:52 PM

On my 1987 300D (W124 chassis), the shift quadrant is illuminated by a separate bulb. You remove the wood piece of the console to get at it, not too bad a job.

I've had the octopus in my W123 out and don't think it illuminates the shift quadrant. It appears the octopus is just for the upper row of switches, above the ACC pushbuttons.

I would think the 126 would be similar.

angst · #8 02-20-2007, 10:11 PM

Thoresn. Im afraid it appears you are spot on. There is one fiber wire going into the octopus that has a frayed section about an inch away from the octo. The sheath on this looks to be a match to the one going to the shifter.
I guess the fiber cable can't be cut back to a shorter length?
Retro fitting some sort of LED lights into the little ports on the left of the shifter box and powering them from the wires running to the window switches seems like a viable option and doesn't seem like all that much work after the other effort in all this.
That will probably wait though. Some coins have fallen into the shift boot and wont let it go into park. Now I have to take the black box off. Grrr

On the plus side of all this. I went and checked my headlights. On low beam one click out turns on the yellow lights in front on. Ive had this car for years and didn't know I had "fog lights" on demand. I just thought the yellow lights were on all the time.
Two clicks out doesn't do anything. By 'rear fog light' does that actually mean a fog light in the tail lights pointing backwards? What purpose does that serve?
If I have the two click out type of headlight switch can I keep pulling to pull it off to inspect the light underneath?

Eskimo · #9 02-20-2007, 10:25 PM

Quote:

Originally Posted by angst

Two clicks out doesn't do anything. By 'rear fog light' does that actually mean a fog light in the tail lights pointing backwards?

Yes. As noted in earlier posts, cars built for the U.S. market didn't have that fog light.

Quote:

Originally Posted by angst

What purpose does that serve?

It is to be seen by drivers following you - to make it easier for them to know your vehicle is there.

Jeremy5848 · #10 02-21-2007, 01:27 AM

My '85 indeed has two click-out positions and the second one doesn't do anything. Didn't know that until just now. (I've also co-opted the rear fog bulb position for an extra tail light.) Is the rear fog lamp wire still in the wiring harness, taped off somewhere? Just curious!

My wife's '87 has only one click-out position, incidentally.

thorsen · #11 02-21-2007, 08:31 AM

Quote:

Originally Posted by angst

Retro fitting some sort of LED lights into the little ports on the left of the shifter box and powering them from the wires running to the window switches seems like a viable option and doesn't seem like all that much work after the other effort in all this.

That's exactly what I did. I removed the entire shifter block, slid out the PRNDSL lettering, drilled holes through the plastic underneath them (for the light to shine through), and then glued LEDs in place using GOOP. Don't use normal light bulbs (they get too hot).