See also:

Tire Terminology And Definitions
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Replacement Keys
NOTE: Only keys that have been programmed to the vehicle electronics can be used to start the vehicle. Once a Sentry Key has been programmed to a vehicle, it cannot be programmed to any other veh ...

For checking and restoring pressure only
The compressor can be also used just for restoring pressure. Disconnect the quick connection and connect it directly to the tyre valve; in this way the cylinder is not connected to compressor and ...