• | The condition may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections . |
• | Ensure that the panel vents are in the OPEN position for proper diagnosis. |
• | Inspect the air delivery system for the following conditions: |
- | An obstruction to the airflow |
- | Air leaks |
- | Misaligned air ducts |
- | Broken or binding linkages or doors |
• | If the scan tool indicates that the Door Actual parameter is 5-10 counts from the Commanded Door parameter, then perform the recalibration procedure for the HVAC door actuators. Refer to Actuator Recalibration . |
• | Recirc will only operate for approximately 10 minutes when selected. After 10 minutes the recirc door switches to the outside air position. The tone of the blower and the velocity of the air speed may be noticeably different when the recirc actuator switches positions. This is a normal condition. If excessive air speed change is noticed inspect the cabin air filter for contamination or blockage. |
Step | Action | Yes | No |
---|---|---|---|
Schematic Reference: HVAC Schematics Connector End View Reference: HVAC Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 |
Is the blower motor OFF? | Go to Step 3 | Go to 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? | Go to Step 4 | Go to Blower Motor Inoperative |
4 | Does the blower motor operate in each speed position? | Go to Step 5 | Go to Blower Motor Malfunction |
5 |
Does the scan tool indicate that the Mode Switch parameter changes state? | Go to Step 6 | Go to Step 8 |
6 |
Does the recirculation door move from the recirculation position to the outside air position? | Go to Step 7 | |
7 |
Does air flow from the auxiliary outlets? | Go to Diagnostic Aids | |
8 | Inspect for poor connections at the harness connector of the HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 10 | Go to Step 9 |
9 | Replace the HVAC control module. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 10 | -- |
10 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |