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 InformationTire 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 ...
Vehicle Messages
DIC messages display when the status of the vehicle has changed and action may
be needed to correct the condition. Multiple messages appear one after another.
All messages should be taken seriously.
Vehicle messages appear as code numbers. The owner manual indicator and service
vehicle soon li ...
Reduced Engine Power Light
The reduced engine power light should
come on briefly as the engine is started. If it does not come on, have the vehicle
serviced by your dealer.
This light, along with the malfunction indicator lamp, displays when a noticeable
reduction in the vehicle's performance occurs.
The vehicle c ...