I have a 2000 S500 with a 3/99 build date, the a/c works but not real well. Dealer has already taken the dash out and done some work, I don't believe the evaporator was upgraded, from what I am told the evaporator hose in early models was pinched during installation in a lot of the cars, causing a restriction, and that is what was fixed on my car. If anyone is aware of the service bulletin number referencing an upgrade, or an upgraded evaporator part number (if there is one) I would appreciate any info. Dealer tells me that this hose replacement is the only available upgrade, that no upgrade for the evaporator exists. They are going to take a second look at the car for me however, as it still doesn't cool off too well, even when set as cold as it will go and with fan on max. Thanks in advance for any info!