Vehicle and Power Issues
OnStar services require a vehicle electrical system, wireless service, and GPS satellite technologies to be available and operating for features to function properly. These systems may not operate if the battery is discharged or disconnected.
See also:
Engine Heater
The engine coolant heater, if available, can help in cold weather conditions at or below −18°C (0°F) for easier starting and better fuel economy during engine warm-up.
Plug in the coolant hea ...
Brake System Warning Light
The vehicle’s hydraulic brake system is divided into two
parts. If one part is not working, the other part can
still work and stop the vehicle. For good braking both
parts need to be working.
...
Recommended Fluids andLubricants
Fluids and lubricants identified below by name,
part number, or specification may be obtained from
your dealer.
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