Germanstar.net has the sensors for $60. I have a dis-similar problem. The shop (non mercedes) installing my compressor did not know they have to put the switch from the old to new (rebuilt) compressor. Since I supplied the part, they said I was supposed to tell'em to do it. now they have to discharge the system put the switch on, and I will connect it. By the way, does anybody knows if, in fact, changing the speed sensor will discharge the system? also, it does not appear that we will have to take the compressor out (a 3 hour job).
1985 190D 2.2l Sold-to Brother-in-law
1996 Mustang 3.8l -"thinks it's a sports car"
1988 Grand Wagoneer - Sold (good home)
1995 Grand Cherokee Ltd -"What was I thinking??!!"