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For 1990-2009 cars only

All-Wheel Drive System Inoperative and DTC C0550 Set - keywords axle control differential disable drive module rear unavailable

Subject:All-Wheel Drive System Inoperative and DTC C0550 Set

Models:2008-2009 Buick Enclave
2007-2009 Chevrolet Equinox
2007-2009 GMC Acadia
2007-2009 Pontiac Torrent
2007-2009 Saturn Outlook
2008-2009 Saturn Vue
2007-2009 Suzuki XL-7
Equipped With All Wheel Drive



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Some customers may comment that the All Wheel Drive System may become inoperative with a "Service All Wheel Drive" (Service AWD) light ON. Customers may also comment of various concerns that may be related to a low battery such as but not exclusive to a no crank or slow engine crank concerns or may have recently had to have the vehicle jump started. The vehicle is still operational in two wheel drive mode.Technicians may find DTC C0550 set as current or history in the clutch control module (CCM). This may occur due to low voltage presence in the system.

Recommendation/Instructions:

If the DTC C0550 is stored in the CCM as current or in history follow the steps below prior to replacement of the CCM.

1. Verify that C0550 is set as current or history in the CCM.

2. Check battery voltage level to be above 9 volts. If battery voltage level is low, perform a charging system diagnosis, parasitic draw test and battery load test and repair as necessary.

3. Clear DTCs and turn OFF ignition for at least 2 minutes.

4. Turn ignition ON and wait for 40 seconds if the DTC C0550 does not reset in the CCM it may have been induced by a low voltage concern. If DTC C0550 resets as current, follow normal diagnostic procedure published in SI.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.