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Test H: Too Cold In Vehicle

WARNING: This page is about a different car, the 2002 Buick Regal and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
  1. If diagnostic system check was not performed, go to DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTICS SYSTEM. If diagnostic system check was performed, go to next step.
  2. Place blower motor switch in each speed position. If blower motor operates in any speed position, go to next step. If blower motor does not operate in any speed position, see TEST C: BLOWER MOTOR INOPERATIVE .
  3. If blower motor operates in desired speeds, go to next step. If blower motor does not operate in desired speeds, see TEST D: BLOWER MOTOR MALFUNCTION .
  4. Inspect heating and cooling systems for low coolant level, loose or worn accessory drive belt, leaking or kinked radiator hoses, missing radiator cap pressure seal or leaking radiator cap. If any conditions specified are found, repair as necessary. When repairs are complete, go to step  18. If no problem is found, go to next step.
  5. Start engine. Place blower motor switch in maximum speed position. Place mode switch in maximum position. If recirculation door moves to recirculation position, go to next step. If recirculation door does not move to recirculation position, see TEST A: AIR DELIVERY IMPROPER .
  6. Place mode switch in VENT or HTR positions. If A/C compressor operates, see TEST E: COMPRESSOR CLUTCH DOES NOT DISENGAGE . If A/C compressor does not operate, go to next step.
  7. Observe left and right temperature actuator drive shafts. Place air temperature switch from coldest position to warmest position. If left and right temperature actuator drive shafts rotate, go to next step. If left and right temperature actuator drive shafts do not rotate, go to step  9.
  8. Inspect air temperature door and air temperature actuator for misalignment, broken or binding linkages, an obstruction that prevents air temperature door from operating within its full range of motion, missing or misaligned seals of air temperature door. If any condition described is found, repair as necessary. When repair is complete, go to step  18. If any condition described is not found, go to next step.
  9. Check suspect air temperature actuator ignition 3 voltage circuit for an open or high resistance. See WIRING DIAGRAMS . If an open or high resistance is found, repair as necessary. When repair is complete, go to step  18. If short to ground or high resistance is not found, go to next step.
  10. Check suspect air temperature actuator ground circuit for an open. See WIRING DIAGRAMS . If an open is found, repair as necessary. When repair is complete, go to step  18. If an open condition is not found, go to next step.
  11. Check suspect air temperature door control circuit of air temperature actuator for short to voltage, short to ground, open or high resistance. See WIRING DIAGRAMS . If short to voltage, short to ground, open or high resistance is found, repair as necessary. When repair is complete, go to step  18. If short to voltage, short to ground, open or high resistance is not found, go to next step.
  12. Ensure HVAC control module connector is connected. Turn ignition on. Using a DVOM connected to ground, measure suspect actuator door control circuit voltage. See WIRING DIAGRAMS . Place air temperature switch from coldest to warmest position. If measured voltage is between zero to 12 volts with a smooth transition between COLD and HOT, go to step  15. If measured voltage is not between zero to 12 volts with a smooth transition between COLD and HOT, go to next step.
  13. Check suspect air temperature actuator harness connector for poor connections. If poor connection is found, repair as necessary. When repair is complete, go to step  18. If poor connection is not found, go to next step.
  14. Inspect suspect air temperature actuator door and any attaching linkage for binding or any condition preventing drive shaft rotation. If any condition described is found, repair as necessary. When repair is complete, go to step  18. If any condition described is not found, go to step  16.
  15. Check HVAC control module harness connector for poor connections. If poor connection is found, repair as necessary. When repair is complete, go to step  18. If poor connection is not found, go to step  17.
  16. Replace suspect air temperature actuator. See ACTUATORS  under REMOVAL & INSTALLATION. When repairs are complete, go to step  18.
  17. Replace HVAC control module. See HVAC CONTROL MODULE  under REMOVAL & INSTALLATION. Perform re-calibration procedure for HVAC control module. See ACTUATOR & HVAC CONTROL MODULE RE-CALIBRATION  under ADJUSTMENTS. When repairs are complete, go to step  18.
  18. Operate system to verify repair. If condition is corrected, system is okay. If condition is not corrected, go to step  2.
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