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 InformationTorque Lock (Automatic Transmission)
If you are parking on a hill and you do not shift the transmission into P (Park)
properly, the weight of the vehicle may put too much force on the parking pawl in
the transmission. You may find it difficult to pull the shift lever out of P (Park).
This is called “torque lock.” To prevent torque ...
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 ...
TPMS Malfunction Light
The TPMS will not function properly if one or more of the TPMS sensors are missing
or inoperable. When the system detects a malfunction, the low tire warning light
flashes for about one minute and then stays on for the remainder of the ignition
cycle. The malfunction light comes on at each ign ...