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Test H: Blower Motor Malfunction

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  1. Perform SYSTEM OPERATION CHECK  under TROUBLE SHOOTING. Go to next step.
    2. NOTE: This step will determine if one or more blower speeds are inoperative.
  2. Turn ignition on. Position mode selector to the VENT position. Place the blower motor switch in each speed position. Does the blower motor operate in each speed position? If so, check for intermittent and poor connections. If not, go to next step.
    3. NOTE: This step determines if there is battery positive voltage at the blower motor resistor assembly.
  3. Turn ignition off. Disconnect the blower motor resistor assembly connector C1. Turn ignition on. Connect a test light between the battery positive voltage circuit of the blower motor resistor assembly and ground. Does the test light illuminate? If so, go to next step. If not, go to step  6.
    4. NOTE: This step tests for voltage in each blower motor control circuit.
    NOTE: Ensure the blower motor switch is in the correct speed position for the blower motor control circuit being tested.
  4. Turn ignition off. Disconnect the blower motor resistor assembly connector C1. Turn ignition on. Probe each blower motor control circuit with a test light that is connected to ground. Place the blower motor switch in the appropriate speed position for the blower motor control circuit being tested. Does the test light illuminate in each speed position? If so, go to next step. If not, go to step  7.
    5. NOTE: This step tests for an open in the blower motor resistor assembly.
  5. Turn ignition off. Connect the blower motor resistor assembly connector C1. Disconnect the blower motor. Turn ignition on. Probe the blower motor voltage circuit of the blower motor with a test light that is connected to ground. Place the blower motor switch in each speed position. Does the test light illuminate in each speed position? If so, go to step  8. If not, go to step  9.
  6. Repair the battery positive voltage circuit to the blower motor resistor assembly for an open or short to ground. After repairs are complete, go to step  11.
  7. Check the appropriate blower motor control circuit for an open. Did you find and correct the condition? If so, go to step  11. If not, go to step  10.
  8. Replace the blower motor. See BLOWER MOTOR  under REMOVAL & INSTALLATION. After repairs are complete, go to step  11.
  9. Replace the blower motor resistor assembly. See BLOWER MOTOR RESISTOR  under REMOVAL & INSTALLATION. After repairs are complete, go to step  11.
  10. Replace the HVAC control assembly. See HVAC CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. After repairs are complete, go to next step.
  11. 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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