Turn the ignition switch ON (II), and check the same terminals for voltage. Is there any voltage?
YES | - | Repair any short to power in the wire(s) between the climate control unit and the driver's air mix control motor. This short also damages the climate control unit. Repair the short to power before replacing the climate contorol unit.■
NO | - | Substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit .■