RAM 1500 Owner's Manual page 48

46 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE
To Lock The Vehicle's Doors:
With one of the vehicle's Passive Entry RKE transmitters
within 5 ft (1.5 m) of the driver or passenger front door
handles, push the door handle LOCK button to lock all
doors.
Push The Door Handle Button To Lock
Do NOT grab the door handle when pushing the door
handle lock button. This could unlock the door(s).
Do NOT Grab The Door Handle When Locking