HVAC System Unable to Maintain Desired Temperature Inside Vehicle (Update HVAC Control Module Software)
| Subject: | HVAC System Unable to Maintain Desired Temperature Inside Vehicle (Update HVAC Control Module Software) |
| Models: | 2007 Chevrolet Monte Carlo |
| 2007-2008 Chevrolet Impala |
| with Automatic Control HVAC System (RPO C67) or Manual Control HVAC System (RPO CJ3) |
Do This | Don't Do This |
|---|---|
Update the HVAC control module software. | DO NOT replace the HVAC control head or the temperature door actuators. |
Condition
Some customers may comment that the temperature selected on the HVAC control head is not being maintained inside the vehicle.
Cause
This condition may be caused by the temperature doors losing their positions.
Correction
Important: There are two calibrations part numbers that are valid for HVAC. Read the descriptions and RPO Codes to determine the correct calibration for your vehicle.
A new calibration has been released that periodically relearns the temperature door positions and prevents the doors from becoming lost. Technicians are to reprogram the HVAC control module with the updated software calibration using SPS. This new service calibration is available on TIS2WEB.
It is recommended that the HVAC actuators be recalibrated after the HVAC control module software is updated. Refer to Actuator Recalibration in the HVAC Control Module Programing and Setup section of SI for more information. When completed, the command state for the actuators will change from "None" to "On".
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
|---|---|---|
D9711* | Reprogram HVAC Control Module | 0.4 hr |
Add | Diagnosis Time: You may claim up to the allowable labor hours depending on actual time performing diagnosis (includes time for actuator recalibration) | 0.00-0.3 hr |
*This is a unique labor operation for bulletin use only. It will not be published in the Labor Time Guide. | ||
