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 ...

Checking the Fluid Level
Prepare your vehicle as follows: 1. Park your vehicle on a level place. Keep the engine running. 2. With the parking brake applied, place the shift lever in PARK (P). 3. With your foot on the b ...

How to Detect a Tamper Condition
If is pressed and the horn sounds, an attempted break-in occurred while the system was armed. If the alarm has been activated, a message will appear on the DIC. See Anti-theft Alarm System Messa ...