Dash Lighting Problem
 

Some one please help me.........

I am having problems with my Dash lights THEY DONT TURN ON, i dont if its a fuse but they wont turn on!!!. :confused:

My head lights work Fine but the Dash lights dont turn on at night and i cant even see wut speed i am going ( i was pulled over the other night by a cop going 75 on free way in my 300D Turbo diesel :rolleyes: )

The only interior lighting i have is the Light near the middle mirror and my radio... :confused:

Please help me it would save me a alot of tickets, when i am driving at night hahaha :)

your rheostat or dash dimmer is toast.

chances are its your dash rheostat (dimmer switch). Remove the cluster and replace it with a new one -or- take two brake sensor wires, cut off the heads, solder them together and plug them in place of the switch on the back of the cluster. I like this idea better anyways since your lighting choices with the original switch are only "slightly dim" and "very dim"...

Well, he didn't even imply that he knew he had a dimmer switch for the dash lights. Maybe it isn't even turned on. The tripmeter reset button is also the dimmer switch for the dash lights. Do you know that and have you tried jiggling it? Sorry, but need to ask the obvious first.

Len

Both the W115 and the W123 that I previously owned needed the dimmer switch rotated full travel back-and-forth to get the instrument panel lights to come on. The W115 was really bad. The dimmer switch is just a wrapped-wire rheostat internally, and the contact and/or the wire core gets oxidized over time and no longer conducts electricity. Simply twisting the switch fully on and off about 100 times (literally, maybe more in the case of my W115) cleaned it enough that the instrument lights would work.

No not the dimmer switch
 

no its not the dimmer switch

How do you know....is it working now.......ALL the juice goes through it for the dash lights.....it goes open (common failure) and no juice gets through.

Either hot-wire the switch to make sure - or replace a bulb or two, and see if that lights anything up.

Have you pulled the cluster to see first hand?

It has to be the rheostat.....I recently lost my fuse for those lights, and you lose a lot more than just the dash lighting, you also lose most of the exterior lights too except for the left side markers. Amazingly I made it home w/out a cop getting on me for having only one little light on in back :D

thxs
 

Thanks

I'm sorry, but can you elaborate on this. I mean, where exactly is the switch? Well, I know, maybe I'll take a picture of my gauge on which the rheostat is mounted and you can point out which is the switch. I just lost my rheostat and the only means by which I can restore lights to my dash are to purchase a new rheostat or do what you said you did.

sorry-

Pull out your cluster, on the side with the fuel gauge, on the back is the rheostat, held in by 2(?) screws, its about 1 sq inch in size, white (porcelin?) and has a spring inside it thats visible (its directly behind where the dimmer knob is on the front side).

take the dimmer switch off and put the jumper wire between the two contact pegs that are now exposed.

had same problem
 

http://instrument.articles.mbz.org/renew/

A few notes:
1. It is NOT necessary to remove the steering wheel in order to pull out the instrument cluster, at least on a 126 body. It's a tight fit, but it can be done. The factory manual says that you should pull the wheel, but you don't have to.
2. Rotating your dimmer enough times may bring it back to life, but the number of rotations could be more than you ever imagined (100 sounds like a lot, buy it'd actually a conservative number). Once I was able to look inside mine, I realized that it would have taken a long, long time to remove all the oxidation by rotating the handle.
3. $53 list for a damn rheostat? I know this is MB parts business, but still: SHAME. :shame: :shame: :shame:

John,

Thanks for further explaining the process. I'll definitely give that a shot.

Rurik, funny, I used that same website's instructions to freshen up my dash and that included rebuilding my rheostat. That rheostat is the one that is gone now (http://www.peachparts.com/shopforum/tech-help/116618-lost-my-dash-rheostat-literally.html?highlight=lost+rheostat). And yeah, I never had to remove my steering wheel in order to get to the instrument cluster. In fact I have removed and returned my instrument cluster several times without every touching the steering wheel.

If I can get a rheostat at a reasonable price, I'll just get one but if I have to pay some insane price for one, then I'll just do John's soldering trick. End of story.

just solder it.. then do this..
http://www.peachparts.com/shopforum/diesel-discussion/111414-just-sharing-my-dash-lighting-project.html

:D