Q I have a 2007 GMC Envoy. In the winter the "service StabiliTrak" light comes up on the dash. In summer it does not come up often, maybe once or twice all summer, but in winter it comes on once or twice a week. To reset the light you have to turn off the ignition and restart the Envoy. I had a scan done to check for codes, but there weren't any.
The problem occurs when the vehicle rocks coming out of a driveway or when making a sharp turn to the left while backing up. Can you shed some light on this problem?
A You may be in luck. My Alldata automotive database pulled up service bulletin 08-05-25-005, dated October 2008, that describes a dynamic condition similar to what you're experiencing that can trigger the light.
This may be caused by "a software anomaly within the electronic brake control module (EBCM) that allowed the yaw offset to be falsely learned." It means the system has learned to recognize a sudden change in the "yaw" axis as a condition that requires engaging the stability control system.
(Yaw is the change in the car's front-to-back axis relative to the direction of travel.)
In this case, the system thinks the vehicle is beginning to spin or slide and tries to stabilize the vehicle.
The bulletin calls for the dealer to reprogram the module with updated software. If the vehicle is still covered by warranty, so would this update.
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