Engine Controls - A/C Not Cold Enough
TECHNICALBulletin No.: 09-01-38-001A
Date: June 10, 2009
Subject: A/C System Pressure Relief Valve (PRV) Release Event, Insufficient Cooling From A/C Vents (Reprogram Engine Control Module (ECM), Recover Refrigerant and Recharge A/C System)
Models:
2008-2009 Chevrolet Captiva Sport (Export)
2008-2009 Saturn VUE
Equipped with Engine RPOs LE5, LY7, LZ4
Please Refer to GMVIS
Supercede:
This bulletin is being revised to update the Warranty Information. Please discard Corporate Bulletin Number 09-01-38-001 (Section 01 - HVAC).
Condition
Some customers may comment that the A/C system does not get cold enough.
Some customers may also comment that they saw and/or heard some type of vapor release coming from the engine compartment when walking up to the vehicle, after using the Remote Start feature.
Cause
This condition may be caused by the calibration in the ECM causing the A/C clutch to engage too quickly after the engine starts. This may result in a pressure release event to occur at the pressure relief valve (PRV). The A/C refrigerant charge may become too low, which would lead to a lack of proper cooling inside the vehicle.
Correction
Important
Do not replace the ECM for any of the following conditions.
Customer Witnesses or Hears a PRV Event
If the customer comments on a lack of cooling from the A/C vents, and states that they witnessed and/or heard a PRV release event, then perform the following procedure before recovering and recharging the A/C system:
1. A revised calibration has been released to address this condition. Reprogram the ECM using the Service Programming System (SPS) with the latest calibration available on TIS2WEB. Refer to the SPS procedures in SI.
2. When using a multiple diagnostic interface (MDI) for reprogramming, ensure that it is updated with the latest software version.
3. When using a Tech 2(R) for reprogramming, ensure that it is updated with the latest software version.
4. During programming, the battery voltage must be maintained within the proper range of 12-15 Volts. Only use the approved Midtronics(R) PSC 550 Battery Maintainer (SPS Programming Support Tool EL-49642) or equivalent during programming.
5. Recover and recharge the A/C system. Refer to Refrigerant Recovery and Recharging (Without HP5) in SI.
Customer Did Not Witness or Hear a PRV Event
If the customer comments on a lack of cooling from the A/C vents, and did not witness and/or hear a PRV release event, then perform the following procedure:
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in SI.
Note
Typical compressor PRV (1) location.
2. Inspect the area surrounding the PRV (1) for green dye leakage with the recommended black light and goggles.
3. If fluorescent dye is not observed then diagnose the system using the Air Conditioning (A/C) System Performance Test for the appropriate engine RPO. Refer to SI.
4. If fluorescent dye is observed then perform the following procedure before recovering and recharging the A/C system.
5. A revised calibration has been released to address this condition. Reprogram the ECM using the Service Programming System (SPS) with the latest calibration available on TIS2WEB. Refer to the SPS procedures in SI.
6. When using a multiple diagnostic interface (MDI) for reprogramming, ensure that it is updated with the latest software version.
7. When using a Tech 2(R) for reprogramming, ensure that it is updated with the latest software version.
8. During programming, the battery voltage must be maintained within the proper range of 12-15 Volts. Only use the approved Midtronics(R) PSC 550 Battery Maintainer (SPS Programming Support Tool EL-49642) or equivalent during programming.
9. Recover and recharge the A/C system. Refer to Refrigerant Recovery and Recharging (Without HP5) in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer