Thanks for the info! You are so right, there's hardly any meaningful info on the ADS system online (well, at least none that I could find). I got all the info i know about ADS while watching the dealer mechanic reading the car with the STAR scan tool. Your page is the most comprehensive read on the system I've had so far!

Actually now the problem is worse, it seems the car is on sport/firm mode all the time, even with the warning light off. I asked them to check the damper valves front and rear, so they actuated them by computer. They worked fine then, and voltage on all four were identically normal. No codes at all...only problem we saw via the STAR computer was that every once in a while it could not communicate with the ADS ECU, and these are the times the ADS warning lights go on...

Am going to try to go over the system myself with the help of your link. Maybe start with getting it back to comfort/soft mode. Will post results. Thanks again for the great link!