OnStar Vehicle Diagnostics can perform a vehicle check every month. It will check
the engine, transmission, antilock brakes, and other major vehicle systems. It also
checks the tire pressures, if the vehicle is equipped with the Tire Pressure Monitoring
System. If an On-Demand Diagnostics check is needed, press
, and an Advisor can run a check.
Connections
OnStar Additional InformationChecking Coolant
The vehicle must be on a level surface when checking the coolant level.
It is normal to see coolant moving in the upper coolant hose return line when
the engine is running.
Check to see if coolant is visible in the coolant surge tank. If the coolant
inside the coolant surge tank is boiling, do ...
Tire Inspection
We recommend that the tires, including the spare tire, if the vehicle has one,
be inspected for signs of wear or damage at least once a month.
Replace the tire if:
The indicators at three or more places around the tire can be seen.
There is cord or fabric showing through the tire's rubb ...
Retained Accessory Power (RAP)
These vehicle accessories may be used for up to 10 minutes after the engine is
turned off:
Audio System
Power Windows
The power windows will continue to work for up to 10 minutes or until any door
is opened. The radio will work when the key is in ON/RUN or ACC/ACCESSORY. Once
the key ...