See also:

Universal Remote System Operation
Press and hold the appropriate button for at least half of a second. The indicator light will come on while the signal is being transmitted. ...

If a Crash Occurs
If there has been an injury, call emergency services for help. Do not leave the scene of a crash until all matters have been taken care of. Move the vehicle only if its position puts you in danger, o ...

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, ...