Subject: | All-Wheel Drive System Inoperative and DTC C0550 Set |
Models: | 2008-2009 Buick Enclave |
| 2007-2009 Chevrolet Equinox |
| 2007-2009 Pontiac Torrent |
| 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.