See also:

Setting the Clock
To set the time and date: 1. Turn the ignition key to ACC/ ACCESSORY or ON/RUN, then press , to turn the radio on. 2. Press to display HR, MIN, MM, DD, and YYYY (hour, minute, month, day, and yea ...

Reactivation for Subsequent Owners
Push and follow the prompts to speak to an Advisor as soon as possible after acquiring the vehicle. The Advisor will update vehicle records and will explain the OnStar service offers and options ...

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 ...