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Test K: Too Cold In Vehicle

NOTE: For circuit reference, see CONNECTOR IDENTIFICATION  and/or WIRING DIAGRAMS  .
NOTE: Definition: The temperature can not be adjusted, or heating is insufficient.
  1. Perform DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After check is complete, go to next step.
  2. Turn ignition on. Set mode selector knob to any position except OFF. Set blower switch in each speed position. If blower operates any of its speed positions, go to next step. If blower does not operate at all, go to TEST F: BLOWER MOTOR INOPERATIVE .
  3. If blower operates at all 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. Check engine cooling system for any of the following conditions:
    • Low Coolant Level
    • Loose Or Worn Accessory Drive Belt
    • Leaking Radiator Or Heater Hoses
    • Kinked Radiator Or Heater Hoses
    • Faulty Or Leaking Radiator Cap
    Repair any condition found. After repairs are complete, go to step  18. If no problem is found, go to next step.
  6. Start engine. Place blower switch in highest speed position. Set mode selector knob in OFF, VENT or FLOOR positions. Set temperature control knob to coldest position. If compressor clutch does engage, go to next step. If compressor clutch does not engage, see TEST A: A/C COMPRESSOR CLUTCH DOES NOT ENGAGE .
  7. 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  9.
  8. Inspect the air temperature door and the temperature actuator for the following conditions:
    • Misaligned Air Temperature Actuator
    • Broken Or Binding Linkages Or Air Temperature Door
    • Obstruction That Prevents The Air Temperature Door From Operating Within Its Full Range Of Motion
    • Missing Seals To The Air Temperature Door
    • Misaligned Seals To The Air Temperature Door
    Did you find and correct the condition? If so, go to step  18. If no problem is found, perform heating performance diagnosis, see HEATER PERFORMANCE TEST  under PERFORMANCE TESTS.
  9. Check ignition voltage circuit of the temperature actuator for open or high resistance. Repair as necessary. After repairs are complete, go to step  18. If wire is okay, go to next step.
  10. Check ground circuit of the temperature actuator for open or high resistance. Repair as necessary. After repairs are complete, go to step  18. If wire is okay, go to next step.
  11. Check air temperature door control circuit of the temperature actuator for open, high resistance, short to ground or short to voltage. Repair as necessary. After repairs are complete, go to step  18. If wire is okay, go to next step.
  12. 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 of the temperature 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  15.
  13. Check for poor connections or connector damage at temperature door actuator. Repair or replace as necessary. After repairs are complete, go to step  18. If connections are okay, go to next step.
  14. Check temperature door actuator for damage, binding and/or faulty linkage. Repair or replace as necessary. After repairs are complete, go to step  18. If not problem is found, go to step  16.
  15. Check for poor connections or connector damage at HVAC control assembly. Repair or replace as necessary. After repairs are complete, go to step  18. If connections are okay, go to step  17.
  16. Replace temperature door actuator. See TEMPERATURE DOOR ACTUATOR  under REMOVAL & INSTALLATION. After repairs are complete, go to step  18.
  17. Replace HVAC control assembly. See HVAC CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. After repairs are complete, go to next step.
  18. 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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