Please help!

I'm having the following trouble with my 2004 E500 4MATIC Sport:

The white colored LED display for the climate control temps and fan speeds are very dim. All other displays (navigation, instrument cluster, etc.) are working as they should regarding dimming. For example, when you turn the headlights on the other displays dim or become backlit as needed or they adjust to ambient light, such as when you drive into a tunnel. The A/C settings don't. They are set to the mode that is appropriate for night conditions. They just stopped turning back to bright for daytime viewing.

I have tried shutting off the daytime running lights thru the settings using the steering controls. I have turned the headlight switch to full OFF. Nothing is taking this display out of what I want to call "night mode" or traditional "headlight-on mode." The potentiometer/reset button/dash dimmer **** next to the instrument cluster works fine and it adjusts the backlighting of everything just fine but the A/C display only gets as bright as you would expect it to get for night viewing.

This is a bit complicated to explain here but I have my fingers crossed that someone will decifer what I'm trying to describe and be able to shed some light (pun unintentional) on this situation.

Any help would be greatly appreciated and I would immediately place you on my holiday card mailing list.

Thanks in advance for your input and Happy Holidays!

 

Not very helpful but sounds as though the backlighting has gone bad.
The backlighting is achieved by a matrix of LEDs on this generation of MB (I think without reference to manuals or in fact any experience of E Class!) so its unlikely that all the LED's have gone. Therefore it is possibly something to do with power.
Once again not sure of your fuse layout and whether they are part of the main light switch....which is the case on many MB. If so have you double checked the fuses....with new or use a multimeter...not by eye.
Alternatively it could be an edge connector on the LED board..or other components.... but this would mean taking the display apart.
Stuart

 

Thanks for the help. It turned out to me a bad ribbon wire that connected to the rain/ambient light sensor on the windshield glass. The windshield was recently replaced and the ribbon wire was mishandled and torn. Without this connection the rain detecting wipers ran at a medium delay interval while the switch was in the rain sensing position but worked fine at low and high speed settings. The nav/command screen ran at a medium intensity as well and didn't change brightness at different ambient light levels.

I was able to fuse the broken conductor temporarily while I wait for the new part.
Thanks again for trying!

 

Hi, I too am having the same issue you describe above. Did you replace the ribbon connection yourself or at the dealership.I would love to hear this is a DIY fix. Thanks in advance.

 

Yes, I did replace it and it wasn't too hard..... more in as bit

 

Yes, I first soldered the end of the factory ribbon back together while I waited 4 weeks for the part to come in. Once it came in I was tempted to just leave it alone since the soldered one was just fine but my conscience got the best of me and I swapped it out for the new one.

The ribbon ended (both ends) within the overhead console. I'm trying to remember how it came apart....
1st, the trim around the rear view mirror came off.
Then the mirror was "popped" out of its spring tensioned mount.
Then the overhead light console came down by pressing on two white colored tabs that were inside under the mirror trim cover. It was simple in a hard to find way. In the case of my e55 or e500 (can't remember which one had the problem), there were no screws involved at all. Nor did I have to remove the lensesthat coverthe overhead lights. I found that out after struggling to remove them without damaging them.
The ribbon is delicate but the ends did just pull out without much effort. A dental mirror and a penlight were helpful to figure out how the damn assembly came down but once it came down it was a sinch.
Did you recently have the windshiend glass replaced? I can't think of another reason that the ribbon would have been torn. The sensor on the glass could be bad, but I doubt that (no moving parts, simple design).
I hope this helps..... let me know!
Remember one thing..... NOTHING needed to be forced! If you are tugging or pushing on something a little hard, stop! The Germans are tricky little bastards and the releases are tricky but clever!
Joe G

 

Joe,

Thanks for the update, I really appreciate it. Yes, the windshied was replaced recently. The main thing that bugs me is the display on the climate control is so darned dim. I dont really care for the rain sensing effectanyway, medium intensity would be preferred. So I was thinking about just unplugging the connection. When the cablel is not connected, was this the result, or did you have to solder the wires for the medium intesity?

 

I had to solder the wires to get the displays to come off of their "dim" setting. Disconnecting it didn't work.I definately tried that.
To state the obvious, whoever did the glass is at fault.
Let me know as things progress...
The truth is that the ribbon is likely repairable. Once you get it out, you can make that call.

JG

 

Ill pull the overhead console off tonight, who knows, maybe ill get lucky and the wire is just loose. If I do find that the wire looks good, would it be your guess that the system would need reprogramming or a bad sensor?

Pete

 

Due to how tight the area is, you'll have to fully remove the wire (less than 12" long) to fully inspect it. It is a delicate ribbon that I coudn't find a problem with until I finally took it completely out and looked at it very closely. There are only 3 or four conductors in it.
I'll be shocked if it is the sensor. Once you have that off you'll see how simple the desing is.

I don't think it'll be a program issue at all. At least mine wasn't. I must have cycled the ignition 30 times while it was disconnected and connected and it didn't throw a code or warning. It just prevented the climate illumination from going to "day" mode. Also, you'll notice that the nav is a bit dark as well.

Let me know.
JG