A/C - Poor Performance, Compressor Noise
ENGINEERING INFORMATIONBulletin No.: 09-01-39-005
Date: May 13, 2009
Subject: EI09115 - Poor A/C Performance, A/C Compressor Noise (Engineering Information)
Models:
2009 Cadillac Escalade Hybrid
2008-2009 Chevrolet Silverado Hybrid, Tahoe Hybrid
2008-2009 GMC Sierra Hybrid, Yukon Hybrid
Attention:
Proceed with this bulletin ONLY if the customer has commented about this concern AND the EI number is listed in GMVIS. If the customer has not commented about this condition or the EI does not show in GMVIS, disregard the bulletin and proceed with diagnostics found in published service information. THIS IS NOT A RECALL -- refer to Service Bulletin 04-00-89-053B for more detail on the use of Engineering Information bulletins.
Condition
Important
If the customer did not bring the vehicle in for this issue, DO NOT proceed with this bulletin. ONLY CONTACT THE ENGINEER IF THE DIAGNOSIS LEADS TO AN A/C REPAIR.
Some customers may comment that the vehicle's A/C is not cooling or is not cold enough. Also, the customer may comment that the compressor is noisy when the A/C is turned on or engaged.
Instructions
Important
DO NOT replace the AC compressor.
GM Engineering is attempting to determine the root cause for numerous "No Trouble Found" compressor returns due to insufficient cooling or noise concerns from the customer. Engineering has a need to gather information on vehicles, PRIOR to repair, that may exhibit cooling or noise concerns. Document the following information on the repair order:
For compressor noise, please confirm:
1. The correct refrigerant charge amount.
2. The compressor attachment bolt torques.
3. The high and low side refrigerant pressures.
For compressor performance concerns, please confirm:
1. The 12 Volt fuse condition.
2. Identify all diagnostic codes that are set.
3. If B101D code is set, clear code and check A/C performance.
Once the above has been documented and confirmed and the condition does not result in acceptable A/C compressor operation, please contact the Warranty Manager before continuing with compressor replacement. If the Warranty Manager is unable to return the call within two hours, proceed with the diagnosis and repair based on information found in SI.
Warranty Information
Select the appropriate labor operation based on the instructions completed.
For vehicles repaired under engineering direction, use the table above.
Disclaimer