See also:

Engine Hours
To display the ENGINE HOURS, place the ignition in LOCK/OFF or ACC/ACCESSORY, then press and hold the trip odometer reset stem for four seconds while viewing the ODOMETER. This display shows the total ...

Trip Odometer Reset Stem Menu Items (with DIC Buttons)
Use the trip odometer reset stem to view the odometer and trip odometer. The Language selection and Engine Hours display can also be accessed with the trip odometer reset stem. ...

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, OnS ...