Blower Control Unit
WARNING: This page is about a different car, the 1997 Mercedes-Benz E420, 1997 Mercedes-Benz E320, and 1997 Mercedes-Benz E300. However, it is still accessible from the selected car via links, so may be relevant.
Blower control unit (electric blower control) consists of a transistorized current regulator and a heat sink. In automatic mode, control unit provides stepless control of blower speeds. Blower speed is continuously varied between minimum and maximum speed, depending on control voltage supplied by push button control panel. Control unit switches blower motor off in event of short circuit. Unit is constantly cooled when blower motor is running.