Blower Motor Inoperative - At Any Speed

TEST DESCRIPTION

Steps 1-9:

Steps 10-23:

5. A short to ground in the positive voltage circuit of the blower motor will cause the HVAC BLO fuse to open when high speed (position 5) is requested. It will also cause the thermal protection to open in the blower motor control resistor when low (position 1) or medium (position 2, 3, and 4) speed is requested.
6. This step tests for a short to ground in the blower motor switch circuits. A short to ground in a speed control circuit will cause the A/C BLOWER fuse to open when that speed is selected.
7. If the test lamp illuminates in all positions, the ignition positive voltage circuit of the blower motor switch is shorted to ground.
8. This step tests for a high resistance or an open in the ignition positive voltage circuit of the blower motor switch.
9. This step tests for a high resistance or an open in the ground circuit of the blower motor resistor.
10. This step tests for a high resistance or an open in the positive voltage circuit of the blower motor.
11. This step tests for a high resistance or an open in the ground circuit of the blower motor.
13. A short to ground in the OFF speed control circuit will cause the A/C BLO fuse to open when the blower motor is turned off.