Up for sale is a good used Mercedes W201 blower speed regulator.  A failure of this unit will result in the loss of one or more fan speeds, or an nonoperational climate control unit. This will work on many different mercedes models with automatic climate control system, . List price at M-B USA is nearly $500! get this one for less than you would pay in tax at the dealer! I only sell the OEM units, never aftermarket so they are the same quality as your original. Thanks for looking!