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Test A: Air Delivery Improper

WARNING: This page is about a different car, the 2002 Oldsmobile Intrigue. 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: Air does not flow correctly from the air distribution outlets.
  1. If diagnostic system check was not performed, go to DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. If diagnostic system check was performed, go to next step.
  2. Start the engine. Place the blower motor switch in the OFF position. Is the blower motor OFF? If so, go to next step. If not, go to TEST E: BLOWER MOTOR ALWAYS ON .
  3. 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. In not, go to TEST C: BLOWER MOTOR INOPERATIVE .
  4. Does the blower motor operate at the desired speed in each speed position? If so, go to next step. If not, go to TEST D: BLOWER MOTOR MALFUNCTION .
  5. Install a scan tool. With a scan tool, observe the MODE BUTTON parameter in the Heating and Air Conditioning data list. Activate the mode switch. With a scan tool, observe the FRONT DEFROST Button parameter in the Heating and Air Conditioning data list. Activate the FRONT DEFROST switch. Does the scan tool indicate that both the MODE BUTTON and FRONT DEFROST BUTTON parameters change state? If so, go to next step. If not go to step  15.
  6. Place the blower motor switch in the maximum speed position. Place the mode switch in the VENT position. Place the outside air switch in the ON position. Place the recirculation switch in the ON position. Does the recirculation door operate properly? If so, go to next step. If not go to TEST B: AIR RECIRCULATION MALFUNCTION .
  7. Place the mode switch in each mode position. Place the defrost switch in the DEFROST position. Does the air flow from the correct air distribution outlets in each mode position? If so, problem is intermittent. See INTERMITTENTS  under TROUBLE SHOOTING. If not, go to next step.
  8. Install a scan tool. With a scan tool, observe the VACUUM SOLENOID parameters in the Heating and Air Conditioning data list. Place the mode switch in each position. Does the scan tool indicate that each observed solenoid parameter changes to ON when the corresponding mode is activated? If so, go to VACUUM CONTROL SYSTEM DIAGNOSTIC TEST under SYSTEM TESTS in INTRIGUE article in MANUAL A/C-HEATER SYSTEMS. If not, go to next step.
  9. Turn ignition off. Disconnect the vacuum control assembly. Turn ignition on. Probe the ignition 3 voltage circuit of the vacuum control assembly with a test light that is connected to ground. Does the test light illuminate? If so, go to next step. If not, go to step  16.
  10. Measure the voltage between the ignition 3 voltage circuit of the vacuum control assembly and the applicable solenoid control circuit of the vacuum control assembly. Place the mode switch in the applicable mode position and then OFF. Does the voltage measure near 12 volts (ON) and zero volts (OFF)? If so, go to step  14. If not, go to next step.
  11. Does the voltage remain near 12 volts with each command? If so, go to step  13. If not, go to next step.
  12. Check the appropriate solenoid control circuit of the vacuum control assembly for a short to voltage or an open. Did you find and correct the condition? If so, go to step  19. If not, go to step  15.
  13. Check the appropriate solenoid control circuit of the vacuum control assembly for a short to ground. Did you find and correct the condition? If so, go to step  19. If not, go to next step.
  14. Inspect for poor connections at the harness connector of the vacuum control assembly. Did you find and correct the condition? If so, go to step  19. If not, go to step  17.
  15. Inspect for poor connections at the harness connector of the HVAC control module. Did you find and correct the condition? If so, go to step  19. If not, go to step  18.
  16. Repair the ignition 3 voltage circuit of the vacuum control assembly for an open or high resistance. After repairs are complete, go to step  19.
  17. Replace the vacuum control assembly. See VACUUM CONTROL ASSEMBLY  under REMOVAL & INSTALLATION. After repairs are complete, go to step  19.
  18. Replace the HVAC control module. See HVAC CONTROL MODULE . After repairs are complete, go to step  19 under REMOVAL & INSTALLATION.
  19. 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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