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Test F: Blower Motor Inoperative

NOTE: For circuit reference, see CONNECTOR IDENTIFICATION  and/or WIRING DIAGRAMS  .
NOTE: Definition: The blower motor is inoperative in all speed positions.
  1. Did you review the DESCRIPTION & OPERATION  and perform SYMPTOM DIAGNOSIS? If so, go to next step. If not, see SYMPTOM DIAGNOSIS  under TROUBLE SHOOTING.
  2. Turn ignition on. Place mode switch in vent position. Place blower motor switch in each speed position. If blower motor operates in any speed position, go to TEST G: BLOWER MOTOR MALFUNCTION . If blower motor does not operate in any speed position, go to next step.
  3. Turn ignition off. Disconnect blower motor. Turn ignition on. Connect a test light between blower motor supply voltage circuit of blower motor and ground. Place blower motor switch in minimum speed position. If test light illuminates, go to next step. If test light does not illuminate, go to step  5.
  4. Check for an open or high resistance in Black wire between blower motor connector terminal "B" and chassis ground G117. Repair Black wire as necessary, then go to step  16. If circuit is okay, go to step  10.
  5. Turn ignition off. Disconnect blower motor resistor. Turn ignition on. Place blower motor switch in minimum speed position. Connect a test light between low blower motor control circuit of blower motor resistor and ground. If test light illuminates, go to step  8. If test light does not illuminate, go to next step.
  6. Check for open or high resistance in low blower motor control circuit of the blower motor resistor. Repair as necessary, then go to step  16. If circuit is okay, go to next step.
  7. Turn ignition off. Disconnect HVAC control assembly connector C2. Turn ignition on. Connect a test light between the ignition voltage circuit of HVAC control assembly and ground. If test light illuminates, go to step  11. If test light does not illuminate, go to step  12.
  8. Check for an open, high resistance or short to ground in blower motor supply voltage circuit between the blower motor and the blower motor relay. Repair as necessary, then go to step  16. If circuit is okay, go to next step.
  9. Check blower motor relay harness connector for loose wires and/or poor connections. Repair as necessary, then go to step  16. If wiring and connections are okay, go to step  13.
  10. Check blower motor harness connector for loose wires and/or poor connections. Repair as necessary, then go to step  16. If wiring and connections are okay, go to step  14.
  11. Check HVAC control assembly harness connector for loose wires and/or poor connections. Repair as necessary, then go to step  16. If wiring and connections are okay, go to step  15.
  12. Repair ignition voltage circuit of HVAC control assembly. After repairs are complete, go to step  16.
  13. Replace blower motor relay. See BLOWER MOTOR RELAY  under REMOVAL & INSTALLATION. After repairs are complete, go to step  16.
  14. Replace blower motor. See BLOWER MOTOR  under REMOVAL & INSTALLATION. After repairs are complete, go to step  16.
  15. Replace HVAC control assembly. See HVAC CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. After repairs are complete, go to next step.
  16. Operate system to verify repair. If system does not operate properly, go to step  3. If system operates correctly, test is complete.
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