See also:

Diagnostics
OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the vehic ...

Transmission Messages
SERVICE 4 WHEEL DRIVE If the vehicle has four-wheel drive, this message may display if a problem occurs with the four-wheel-drive system. If this message appears, stop as soon as possible and turn of ...

Potential Issues
Some OnStar services are disabled after five days. OnStar cannot perform Remote Door Unlock or Stolen Vehicle Assistance after the vehicle has been off continuously for five days. After five days, ...