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Test F: Blower Motor Inoperative

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  1. Perform SYSTEM OPERATION CHECK  under TROUBLE SHOOTING. Go to next step.
    2. NOTE: This step tests for blower motor operation in any speed setting.
  2. Turn ignition on. Place the mode selector to the VENT position. Place the blower motor switch in each speed position. Is the blower motor inoperative in each speed position? If so, go to next step. If not, check for intermittent and poor connections.
    3. NOTE: This step tests for voltage at the blower motor.
  3. Turn ignition off. Disconnect the blower motor. Turn ignition on. Connect a test light between the blower motor supply circuit and ground. Place the blower motor switch in the minimum speed position. Does the test light illuminate? If so, go to next step. If not, go to step  5.
    4. NOTE: This step tests for a possible open in the blower motor ground circuit.
  4. Connect a test light between the blower motor supply circuit and the blower motor ground circuit. Place the blower motor switch in the minimum speed position. Does the test light illuminate? If so, go to step  9. If not, go to step  8.
    5. NOTE: This step tests for output voltage from the blower motor switch.
    NOTE: The blower motor switch must be in the correct speed position for the blower motor control circuit being tested. Failure to do this will result in a misdiagnosis.
  5. Turn ignition off. Disconnect the blower motor resistor assembly connector C1. Turn ignition on. Place the blower motor switch in the minimum speed position. Probe the low blower motor control circuit with a test light that is connected to ground. Does the test light illuminate? If so, go to step  10. If not, go to next step.
  6. Check the HVAC module ignition 3 voltage circuit for an open, high resistance or a short to ground. Did you find and correct the condition? If so, go to step  15. If not, go to next step.
  7. Check each blower motor control circuit for a short to ground. Did you find and correct the condition? If so, go to step  15. If not, go to step  11.
  8. Check the ground circuit of the blower motor resistor assembly for an open or high resistance. Did you find and correct the condition? If so, go to step  15. If not, go to step  10.
  9. Inspect blower motor harness connector for poor connections. Did you find and correct the condition? If so, go to step  15. If not, go to step  13.
  10. Inspect blower motor resistor assembly harness connectors for poor connections. Did you find and correct the condition? If so, go to step  15. If not, go to step  14.
  11. Inspect HVAC control assembly harness connectors for poor connections. Did you find and correct the condition? If so, go to step  15. If not, go to next step.
  12. Replace HVAC control assembly. See HVAC CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. After repairs are complete, go to step  15.
  13. Replace blower motor. See BLOWER MOTOR  under REMOVAL & INSTALLATION. After repairs are complete, go to step  15.
  14. Replace blower motor resistor assembly. See BLOWER MOTOR RESISTOR  under REMOVAL & INSTALLATION. After repairs are complete, go to next step.
  15. Operate the system in order to verify the repair. Did you correct the condition? If so, system is okay. If not, go to step  2.
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