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Test K: Too Hot In Vehicle

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2002 GMC Savana Special, 2002 GMC Savana Camper Special, 2002 GMC Savana, 2002 Chevrolet RV Cutaway, and 2002 Chevrolet Cutaway. 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: The manufacturer does not separate testing by "heater only" or "air conditioned" vehicles. References to air conditioning operations or repairs may not apply to vehicles without air conditioning. References to some components also may not apply to vehicles without air conditioning.
NOTE: Definition: Temperature can not be adjusted, or cooling insufficient during A/C operation.
  1. Did you review the DESCRIPTION  and OPERATION  and perform the necessary inspections? If so, go to next step. If not, go to DESCRIPTION  and OPERATION  , then go to next step.
  2. Turn the ignition on, with the engine off. Place the mode switch in any position except OFF. Place the blower motor switch in each speed position. Does the blower motor operate in any of the speed positions? If so, go to next step. If not, go to TEST E: BLOWER MOTOR INOPERATIVE .
  3. Does the blower motor operate correctly for each speed position? If so, go to next step. If not, go to TEST F: BLOWER MOTOR MALFUNCTION .
  4. Ensure the blower motor switch is on. Select an air outlet mode. Does air flow out of the selected HVAC outlet ducts? If so, go to next step. If not, go to TEST I: IMPROPER AIR DELIVERY .
  5. When A/C is On, does the customer concern occur? If so, go to next step. If not, go to  8.
  6. Start the engine. Place the blower motor switch in the maximum speed position. Place the mode switch in the BI-LEVEL position. Place the temperature switch in the coldest position. Does the A/C compressor operate? If so, go to next step. If not, see appropriate HVAC COMPRESSOR CLUTCH DOES NOT ENGAGE in SYMPTOM TESTS in MANUAL A/C-HEATER SYSTEMS article.
  7. Perform the refrigerant system performance test. See A/C PERFORMANCE TEST in PERFORMANCE TESTS in MANUAL A/C-HEATER SYSTEMS article. Did you find and correct the condition? If so, go to step  18. If not, go to next step.
  8. Observe the drive shaft of the temperature actuator. Place the temperature switch from the coldest position to the warmest position. Does the temperature actuator drive shaft rotate at all? If so, go to next step. If not, go to step  10.
  9. Inspect the temperature door and the temperature actuator for the following conditions:
    • Misaligned temperature actuator.
    • Broken or binding linkages or temperature door.
    • Obstruction that prevents the temperature door from operating within its full range of motion.
    • Missing seals to the temperature door.
    • Misaligned seals to the temperature door.
    Did you find and correct the condition? If so, go to step  18. If not, concern is intermittent. See SYMPTOM DIAGNOSIS  under TROUBLE SHOOTING.
  10. Check the ignition 3 voltage circuit of the temperature actuator for an open, high resistance or short to ground. Did you find and correct the condition? If so, go to step  18. If not, go to next step.
  11. Check the ground circuit of the temperature actuator for an open. Did you find and correct the condition? If so, go to step  18. If not, go to next step.
  12. Check the temperature door control circuit of the temperature actuator for an open, high resistance, short to ground, or short to voltage. Did you find and correct the condition? If so, go to step  18. If not, go to next step.
    13. NOTE: Ensure that the HVAC control assembly connector is connected during this step in order to avoid misdiagnosis.
  13. Measure the voltage from the temperature door control circuit of the temperature actuator to ground. Place the temperature switch from coldest position to the warmest position. Does the voltage measure between zero volts and battery voltage? If so, go to step  15. If not, go to next step.
  14. Inspect for poor connections at the harness connector of the temperature actuator. Did you find and correct the condition? If so, go to step  18. If not, go to step  16.
  15. Inspect the harness connector of the HVAC control assembly for poor connections. Did you find and correct the condition? If so, go to step  18. If not, go to step  17.
  16. Replace the temperature actuator. See TEMPERATURE ACTUATOR  under REMOVAL & INSTALLATION. After repairs, go to step  18.
  17. Replace the HVAC control assembly. See HVAC CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. After repairs, go to step  18.
  18. 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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