See also:

Warranty
OnStar equipment may be warranted as part of the new-vehicle limited warranty. The manufacturer of the vehicle furnishes detailed warranty information. ...

Engine Oil Additives/Engine Oil Flushes
Do not add anything to the oil. The recommended oils with the dexos specification and displaying the dexos certification mark are all that is needed for good performance and engine protection. ...

Engine Compartment Fuse Block (CTS Wagon)
This fuse block is on the left side of the engine compartment. Lift the fuse block cover to access the fuses. The vehicle may not be equipped with all of the fuses and relays shown. Notic ...