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2000 Models

WARNING: This page is about a different car, the 2001 Pontiac Bonneville and 2000 Pontiac Bonneville. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform diagnostic system check. See DIAGNOSTIC SYSTEM CHECK  under TROUBLE SHOOTING and go to next step.
  2. Connect scan tool and turn ignition on. Use scan tool to perform RECALIBRATE ALL MOTORS command in INSTRUMENT PANEL MODULE SPECIAL FUNCTIONS. Use scan tool to observe CURRENT DTC LIST in INSTRUMENT PANEL MODULE. If scan tool displays any DTCs, see DIAGNOSTIC TROUBLE CODE IDENTIFICATION  table under SELF-DIAGNOSTICS. If scan tool does not display any DTCs, go to next step.
  3. Turn ignition on. Select defrost mode. Ensure defrost outlet on top of instrument panel is not obstructed. Adjust blower speed from minimum to maximum. Use scan tool to observe COMMANDED BLOWER DATA parameter in INSTRUMENT PANEL MODULE data list. If scan tool indicates COMMANDED BLOWER DATA parameter is more than 100 percent, go to step  4 . If scan tool indicates COMMANDED BLOWER DATA parameter is 100 percent or less, see BLOWER MOTOR DOES NOT OPERATE PROPERLY  .
  4. Set blower speed to maximum. Select DEFROST, DEFOG, and PANEL modes. If airflow changes discharge locations, go to next step. If airflow does not change discharge locations, see IMPROPER AIR DELIVERY  .
  5. Ensure ambient (outside) air temperature is greater than 38°F (3°C). Start engine. Adjust driver's side temperature to 90°F (32°C). Select DEFROST mode. Set blower speed to maximum. Turn off passenger HVAC control. Let engine idle at normal operating temperature. If A/C compressor operates, go to next step. If A/C compressor does not operate, see A/C COMPRESSOR CLUTCH CONTROLS - ALL MODELS article.
  6. Use scan tool to observe ECT DATA parameter in POWERTRAIN CONTROL MODULE data list. If scan tool indicates ECT DATA parameter is between 188-208°F (87-98°C), go to next step. If scan tool indicates, ECT parameter is not between 188-208°F (87-98°C), check engine cooling system.
  7. If airflow is warm in DEFROST mode, go to next step. If airflow is not warm, see INSUFFICIENT HEATING in MANUAL A/C HEATER SYSTEMS - TROUBLE SHOOTING article.
  8. If defrost airflow is sufficient and left defrost airflow is similar to right airflow at defroster grille and side window outlets, go to step  11 . If airflow is not sufficient and or left defrost airflow is different from right at defroster grille and side window outlets, go to next step.
  9. Turn engine off. Check for obstructions and proper defrost alignment. If a problem was found, go to step  12 . If no problem was found, go to next step.
  10. Check mode actuator for binding or mechanical failure. See MODE ACTUATOR  under REMOVAL & INSTALLATION. If a problem was found and corrected, go to step  12 . If a problem was not found and corrected, go to next step.
  11. Cover sunload sensor. Start engine. Fully open all instrument panel outlets. Operate system. If system operates properly, system is okay at this time. If system is not okay, perform appropriate symptom test.
  12. Operate system to verify proper operation. If system is not okay, go back to step  2 .
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