See also:

Engine Oil Additives/Engine Oil Flushes
Do not add anything to the oil. The recommended oils with the dexos specification and displaying the dexos certification mark are all that is needed for good performance and engine protection ...

Tips and Troubleshooting Chart
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Anti-theft Alarm System Message
SERVICE THEFT DETERRENT SYSTEM This message displays when there is a problem with the theft-deterrent system. The vehicle may or may not restart so you may want to take the vehicle to your dealer ...