FLOWCHARTS — Flowchart No. 1: Blower motor does not operate at any fan switch position
G-12flowchartTROUBLESHOOTING
FLOWCHARTS
Flowchart No. 1
Flowchart No.
Value1
Symptom
ValueBlower motor does not operate at any fan switch position
Related components
ValueFuse, blower relay, blower motor, resistor, fan switch, wiring harness
System Operation
Blower motor speed is controlled by the fan switch and resistor in the blower unit. When the fan switch is in the OFF position, the motor ground circuit is open and the blower motor does not operate. When the switch is in the first position, current flow from the blower motor is restricted by the resistor, and the blower motor turns at low speed.
Changing the fan switch to the second, third, or fourth positions causes the circuit resistance to decrease and the blower speed to increase.
Step 1
- 1Check the HEATER 30A fuse (circuit breaker) in the joint box.
- 2If the reset button is not out, go to Step 2.
- 3If the reset button is out, check for a short circuit in the harness. Repair as necessary, and then depress the reset button to reset the circuit breaker.