Blower Motor Switch: Testing and Inspection

WARNING: Refer to Air Bags before attempting Steering Wheel, Steering Column, or Instrument Panel component diagnosis or service. Failure to take the proper precautions could result in accidental air bag deployment and possible personal injury.

1. Turn the ignition switch to the On position and check for battery voltage at the fuse in the fuseblock module. If OK, go to Step 2. If not OK, replace the faulty fuse.
2. Turn the ignition switch to the Off position. Remove the heater-A/C control from the instrument panel, but do not unplug the wiring connectors. Turn the ignition switch to the On position. Check for battery voltage at the fused ignition switch output (run) circuit cavity of the heater-A/C mode control switch connector. If OK, go to Step 3. If not OK, repair the open circuit to the fuseblock module as required.
3. Select any one of the heater-A/C mode control positions except Off to turn the system on. Check for battery voltage at the low blower motor driver circuit cavity of the heater-A/C mode control switch connector. If OK, go to Step 4. If not OK, replace the faulty heater-A/C mode control switch.
4. Check for battery voltage at the low blower motor driver circuit cavity of the blower motor switch connector. If OK, go to Step 5. If not OK, repair the open circuit to the heater-A/C mode control switch connector as required.
5. Check for battery voltage at each of the remaining blower motor switch connector cavities as you move the switch to each blower motor speed position. Voltage should be present in each cavity at only one switch position. If OK, see the diagnosis for the blower motor resistor and/or the high speed blower motor relay. If not OK, replace the faulty blower motor switch.