Having issues with intermittent [Service Traction System] light coming on in the middle of a trip. Goes off when I stop then restart the car, only to eventually come on again. Had it looked at once already, but the computer diagnostic test showed nothing. I am now going to wait for the light to come on again to take it in while the light is actively on.

The problems I seem to be having all seemed to have started after I went thru the Onstar upgrade from Analog to Digital. On Friday my whole computer system went nuts and all the light appeared on the dash while driving but went away. Now the Service Traction Control system light comes on and I have no idea if it is real or a phantom reading due to the Onstar upgrade.