LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2003 >> Safari Van Cargo, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 35 (HVAC Systems - Manual) >> Symptom Tests >> Test F: Blower Motor Malfunction

Test F: Blower Motor Malfunction

WARNING: This page is about a different car, the 2002 GMC Savana Special, 2002 GMC Savana Camper Special, 2002 GMC Savana, and 2002 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: For circuit reference, see CONNECTOR IDENTIFICATION  and/or WIRING DIAGRAMS  .
NOTE: Definition: The blower motor operates in at least one, but not all, speed positions.
  1. If review of system operation has been performed, go to next step. If review of system operation has not been performed, see DESCRIPTION  and OPERATION  .
  2. Turn ignition on. Place main HVAC control mode switch in VENT position. Place blower switch in each speed position. If blower motor operates correctly in each speed position, problem is intermittent. Check wiring and connectors for damage and poor connections. If blower motor does not operate correctly in each speed position, go to next step.
  3. Turn ignition off. Disconnect blower motor harness connector. Turn ignition on. Using a test light connected to ground, probe voltage supply terminal (Purple wire) at blower motor harness connector. Place blower switch in each speed position. If test light illuminates in each speed position, go to step  7. If test light does not illuminate in each speed position, go to next step.
  4. Turn ignition off. Disconnect harness connector from blower motor resistor. See Figure. Turn ignition on. Using a test light connected to ground, probe voltage supply terminal (Red wire) at blower motor resistor connector. If test light illuminates, go to next step. If test light does not illuminate, go to step  10.
  5. Using a test light connected to ground, probe each blower motor speed circuit at blower motor resistor connector, while placing blower switch in appropriate speed position for circuit being tested. See WIRING DIAGRAMS . If test light illuminates in each speed position, go to step  8. If test light does not illuminate in each speed position, go to next step.
  6. Check the suspect blower motor control circuit for an open. If an open was found, repair as necessary and go to step  14. If an open was not found, go to step  9.
  7. Check harness connector at blower motor for a poor connection. If a poor connection was found, repair as necessary and go to step  14. If a poor connection was not found, go to step  11.
  8. Check harness connector at blower motor resistor for a poor connection. If a poor connection was found, repair as necessary and go to step  14. If a poor connection was not found, go to step  12.
  9. Check harness connector at main HVAC control assembly for a poor connection. If a poor connection was found, repair as necessary and go to step  14. If a poor connection was not found, go to step  13.
  10. Repair voltage supply circuit (Red wire) to blower motor resistor. See WIRING DIAGRAMS . If repair is complete, go to step  14.
  11. Replace blower motor. See BLOWER MOTORS  under REMOVAL & INSTALLATION. After repairs are complete, go to step  14.
  12. Replace blower motor resistor. See Figure. After repairs are complete, go to step  14.
  13. Replace main HVAC control assembly. See MAIN HVAC CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. If replacement is complete, go to next step.
  14. Operate system to verify repair. If the condition was corrected, system is okay. If the condition was not corrected, return to step  2.
scientia non olet · About LEMON Manuals