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Test J: Too Hot In Vehicle

NOTE: For circuit reference, see CONNECTOR IDENTIFICATION  and/or WIRING DIAGRAMS  .
NOTE: Definition: The temperature can not be adjusted, or the cooling is insufficient during A/C operation.
  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. Set mode selector knob to any position except OFF. Set blower switch in each speed position. If blower operates in any speed positions, go to next step. If blower does not operate at all, go to TEST F: BLOWER MOTOR INOPERATIVE .
  3. If blower operates in any speed positions, go to next step. If blower does not operate at one or more speed positions, go to TEST G: BLOWER MOTOR MALFUNCTION .
  4. Alternately place recirculation door between VENT and MAX A/C positions. If recirculation door moves properly between positions, go to next step. If recirculation door does not move properly between positions, go to TEST D: AIR DELIVERY IMPROPER .
  5. If too hot in vehicle condition occurs when A/C cooling is desired, go to next step. If too hot in vehicle condition occurs when A/C cooling is not desired, go to step  8.
    6. NOTE: For A/C compressor operation, ambient air temperature must be greater than 38°F (3°C).
  6. Start engine. Place blower switch in highest speed position. Set mode selector knob in MAX A/C position. Set temperature control knob to coldest position. If compressor clutch engages, go to next step. If compressor clutch does not engage, see TEST A: A/C COMPRESSOR CLUTCH DOES NOT ENGAGE .
  7. Perform See A/C PERFORMANCE TEST  under PERFORMANCE TESTS. If problem was found and corrected, go to step  19. If A/C system performance is okay, go to next step.
  8. Observe temperature door actuator drive shaft while moving temperature control knob from coldest to warmest position. If drive shaft rotates, go to next step. If drive shaft does not rotate, go to step  10.
  9. Check air temperature door and temperature door actuator for actuator misalignment, binding linkage, obstruction, and missing or damaged seals. Repair or replace as necessary, then go to step  19. If no problem is found, repair faulty connections at air temperature valve door actuator harness connector. After repairs are complete, go to step  19.
  10. Check ignition voltage circuit of the temperature actuator for open or high resistance. Repair as necessary. After repairs are complete, go to step  19. If wire is okay, go to next step.
  11. Check ground circuit of the temperature actuator for open or high resistance. Repair as necessary. After repairs are complete, go to step  19. If wire is okay, go to next step.
  12. Check air temperature door control circuit of temperature door actuator for open, high resistance, short to ground or short to voltage. Repair as necessary. After repairs are complete, go to step  19. If wire is okay, go to next step.
  13. Ensure HVAC control assembly harness connector is properly connected. Turn ignition on. Using DVOM connected to ground, measure voltage of air temperature door control circuit at temperature door actuator. Move temperature control knob from cold to hot positions. DVOM should indicate battery voltage in cold position and zero volts in hot position. If voltage readings are as specified, go to next step. If voltage readings are not as specified, go to step  16.
  14. Check for poor connections or connector damage at temperature door actuator. Repair or replace as necessary. After repairs are complete, go to step  19. If connections are okay, go to next step.
  15. Check temperature door actuator for damage, binding and/or faulty linkage. Repair or replace as necessary. After repairs are complete, go to step  19. If no problem is found, go to step  17.
  16. Check for poor connections or connector damage at HVAC control assembly. Repair or replace as necessary. After repairs are complete, go to step  19. If connections are okay, go to step  18.
  17. Replace temperature door actuator. After repair, check system for normal operation. See TEMPERATURE DOOR ACTUATOR  under REMOVAL & INSTALLATION. After repairs are complete, go to step  19.
  18. Replace HVAC control assembly. See HVAC CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. After repairs are complete, go to next step.
  19. Check system operation. If condition has been repaired, system is okay. If condition is still present, go to step  2. If system operates correctly, test is complete.
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