See also:

To Lock The Doors And Liftgate
Press and release the LOCK button on the RKE transmitter to lock all doors and the liftgate. The turn signal lights will flash and the horn will chirp to acknowledge the lock signal. ...

Fluid Capacities
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Horn With Remote Lock
When this feature is selected, a short horn sound will occur when the RKE transmitter LOCK button is pressed. This feature may be selected with or without the “Flash Lamps with Lock” feature. ...