I've got a 2000 S500 I need to figure out at work, since I'm not very familiar with the W220's common faults so I figured I would ask a few questions. I haven't really checked anything on the car yet. I do have a knock-off Chinese STAR system that I'll bring in once I get an idea of where to start on this thing. I have more important cars to work on first since this car, unfortunately, isn't really in good shape I don't want to waste a bunch of time/money with it.

First and main problem is the gauge cluster is completely dead and does not work at all. It looks like it just stopped working when they were driving. I searched around and saw some mention about 3 transistors melting. Is that the definitive fix for the gauges not working as well or is that only for the backlight going out? Is there something else that works in place of the special tools to remove the cluster? Is the mileage only stored in the cluster or is it stored in another module and read by the cluster? It has supposedly been dead for quite a while (over a year), so I need to know whether or not the mileage will be correct or not when/if I get this cluster working (or if we need to put a used cluster in it) so that can be disclosed.

Second problem is it has a bad battery drain. I replaced the battery when we first got the car in a few weeks ago and I think it was dead again within a day or two. I know the older W203s had an issue with seat modules, but I didn't see anything really common mentioned when I searched the W220 forum.

Last problem (so far at least, I haven't even driven the car yet) is the air suspension on one side drops down literally 5-10 minutes after the car is turned off. This is usually the struts leaking, correct? After the car is started the suspension comes up to normal height.

Any help would be much appreciated. Thanks.

 

Connect the car the star and runs a quick test and it will tell you where your 3 mentioned problems are.