Activate a light viewport. > Viewport navigation controls > Truck Light
Trucking a light
Truck Light moves a target light and its target parallel to the light view, and moves a free light along its XY axis.
To accelerate trucking, hold down the CTRL key.
Note: This button replaces the Pan button when a light viewport is active.
Procedures
To truck a light:
Activate a Light viewport.
Click Truck Light.
The button turns green when it is on.
Drag to move the light and its target.
The camera and its target move parallel to the view plane, which is perpendicular to the camera's line of sight.
Press ESC or right-click to turn off the button.
To constrain trucking to a single axis:
Hold down the SHIFT key.
The truck is constrained to the first axis you use.