There was an earlier post that attributed the problem to the connector on the back of the display.
It suggested that the connection is prone to poor connections due to age, moisture, vibration, acts of Satan, etc.
I know my E320 (2000) seems to almost be perfect in dry warm weather -- and if driven every day. If it's cool, moist and sits around it gets worse. In addition it's not always the same pixels that are OD leading me to the conclusion that the problem is either a connector or a faulty logic circuit somewhere.[!]
I found a very informative company who explained the whole VDO Cluster LED situation to me. There is an electrical connector from the driver to the display that is made of PAPER!! (3M pressure sensitive carbon trace ribbon). The connector could have been made with a better material, but for a few pennies, Mercedes chose to go with paper.
The company Advanced Auto Electronics, Inc. offers to repair the displays and quoted me a price of $275, but the components that would be installed would be the same POS components that VDO originally manufactured with the paper connector. The faults would likely return in about the same time the original components broke down. Good Luck.
The Instrument cluster comes out quite easily if you use the right tools. Two hooks with handles that are inserted in between the cluster and the dash...hook the back of the cluster and pull out. The cluster is held in place by four friction tabs/springs. You just have to work the cluster out! Do a search on eBay for Mercedes tools, you'll see the instrument cluster removal tools advertised. Another place for the tools is Samstag Sales among others. Good Luck.
I have a similar problem on my 99 320 display except that the Left side is less bright than the Right so that the temp is almost invisible in daylight,I must add that paper doesn't seem to be the most sensible material to use in these components but Benz garages have to make money somewhere
i pulled a cluster out of a 2001 e320, and replaced a bunch of the little bulbs (not sure why they were out). and the display lights up like the 4th of july now. the old cluster had the temp and clock displays out, and even with new bulbs, they would not show anything (the display was lit, but numbers just would not show up). so i guess it was a bad odometer cluster. (got the new one from e-klasse - thanks again man!).
Just for information. I was going to pull the cluster and unplug, clean and replug the connector(s) to see if it would fix the problem. Before I could do that, I put it in the shop for a fuel leak around the IP and a non-functioning air conditioner. $2400 dollars later, the leak is gone, the air conditioner is cold and all the led's work again. If you haven't already, I recommend trying to remove and replace the connector. It couldn't hurt.
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