Diagnostics
OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the vehicle is equipped with the Tire Pressure Monitoring System.
If a diagnostics check is needed between e-mails, push 
, and an Advisor can run a check.
See also:
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted or corroded. If wheel nuts keep coming loose, the wheel, wheel bolts, and wheel nuts should be replaced.
If the wheel leaks air, replace it.
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New Vehicle Break-In
Notice: The vehicle does not need an elaborate break-in.
But it will perform better in the long run if you follow these guidelines:
• If you have all-wheel drive, keep your speed at 88 km/h (55 mp ...
Clock
To adjust the time and date:
1. Turn the ignition key to ACC/ACCESSORY or ON/RUN, then press to turn the radio on.
2. Press to display HR, MIN, MM, DD, YYYY (hour, minute, month, day, and year).
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