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 v ...

Fuel Gage
When the ignition is on, the fuel gage tells you about how much fuel you have remaining. Here are four things that some owners ask about. None of these show a problem with your fuel gage: ...

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 ...