Air Conditioning Compressor and/or Serpentine Belt Noise at Vehicle Startup with Ambient Temperature Above 35 Degrees Celsius (95 Degrees Fahrenheit)
| Subject: | Air Conditioning Compressor And/Or Serpentine Belt Noise At Vehicle Startup With Ambient Temperature Above 35° C (95° F) (Reprogram Powertrain Control Module (PCM)) |
| Models: | 2007-2008 Cadillac Escalade Models |
| 2007-2008 Chevrolet Avalanche, Silverado, Suburban, Tahoe |
| 2007-2008 GMC Sierra, Yukon Models |
| with Air Conditioning (RPOs CJ2 or CJ3) |
Condition
Some customers may comment on air conditioning (A/C) compressor and/or serpentine belt noise at vehicle startup with the ambient temperature above 35° C (95° F). Others may describe the noise as a belt chirp or as a thumping/grinding noise coming from the A/C compressor at vehicle startup.
Cause
This condition may be caused by the A/C compressor trying to move liquid refrigerant through the system.
Correction
Do This | Don't Do This |
|---|---|
Reprogram the PCM with an updated calibration. | Do Not replace the compressor, compressor clutch, serpentine belt and/or the belt tensioner. |
A revised calibration has been developed to address this concern. Technicians are to reprogram the Powertrain Control Module (PCM) using SPS with the latest software available on TIS2WEB. Refer to the Engine Control Module Programming and Setup procedures in SI. As always, make sure your Tech 2® is updated with the latest software version.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time | Failure Code |
|---|---|---|---|
J6354 | Powertrain Control Module Engine Reprogramming with SPS | Use Published Labor Operation Time | 93 (Technical Service Bulletin)* |
*Please use the Failure Code 93 for any warranty claims submitted using this bulletin.
