A/C Electronic Blower Regulator Control
WARNING: This page is about a different car, the 1998 Mercedes-Benz C43, 1998 Mercedes-Benz C280, and 1998 Mercedes-Benz C230. However, it is still accessible from the selected car via links, so may be relevant.
Connect socket box and 3-connector test cable to A/C push-button control unit right connector. See Figure. Turn ignition on. Connect DVOM negative lead to socket box terminal No. 19 and positive lead to terminal No. 1. Press fan button. At minimum fan speed, voltage should be greater than .7 volts. At maximum fan speed, voltage should be greater than .5 volts. If voltages are not to specification, check wiring. See WIRING DIAGRAMS .