Instrument Cluster Bulb replacement
Just replaced some bulbs out in my 98 ML320, and even got the clock back. Since there was no sticky here, and no one thread contained all lessons learned, here are some of the more salient ones:
The bulbs used were exact replacements: Autohaus AZ part 62 11 1 391 260. (12V 1.2 watt, brown base included) Get a dozen, they are cheap.
The best instructions were from MarJa , who has some good photos in the original writeup here:
http://www.benzworld.org/forums/w163-m-class/1301171-instrument-cluster-removal.html
My only additions to these suggestions are:
1. Put the key in ignition position II, and using tape, mark all of the bulb locations that you want to replace.
2. Tape also used to cover areas that screws could drop, and to protect the steering wheel column and dashboard from scratches.
3. A Bondo plastic wedge was used to remove panels and avoid scratches and dings.
4. Use needle nose pliers or small standard screwdriver to remove and replace bulbs.
5. Reconnect instrument cable (if battery is still connected) to check bulbs
Be prepared to have a good smile over Carolina’s avatar, but some good learning here:
http://www.benzworld.org/forums/w163-m-class/1465434-instrument-cluster-snafu.html
43sqd and WitekM references and advice:
MB Instructions for R&R are attached, as is diagram of back of cluster.
These are the things that could need resetting, including the radio which you must have the code for. ****So do not proceed until you have the code.****
AFTER DISCONNECTING THE NEGATIVE BATTERY CABLE
1. Code radio.
2. Set time on instrument cluster.
3. If necessary, set time at stationary heater timer
4. Start engine and run at idle. Turn steering wheel from on lock position to the other to activate steering angle sensor.
5. If equipped, normalize tilting/sliding roof. Open sunroof and hold down switch. Sunroof moves to end position and pulls back ¼ turn and stops. If equipped with lamella sliding roof, close roof and keep switch pressed fro 5 to 10 seconds.
6. Normalize power windows. Completely close each window with manual switch. Hold switch in closed position for 5 seconds.
7. If there is no throttle response, turn key to position #2, DO NOT START ENGINE.
Leave in that position for 60 seconds, then turn key off to position O. Wait
10 sec., then start engine.
(For my ML320, I was a heathen, and did not disconnect the battery because I wanted to do a light check on the cluster before reinstallation. Turns out, there is only one signal cable visible during the entire job, no risk of shorting things out.)