See also:

To Resume Speed
To resume a previously set speed, push the RES (+) button and release. Resume can be used at any speed above 20 mph (32 km/h). ...

Power-Up
After switching the ignition key from OFF to either the ON or ACC position, or after a language change, you must wait at least fifteen seconds prior to using the system. ...

Legendary Capability
The all-new Jeep Grand Cherokee offers the new Quadra-Lift air suspension system. The Quadra-Lift system features five height settings for optimum ride performance: Normal Ride Height (NRH): 8.1 ...