Ford F-150 2010 Owner's Manual page 287

Driving
BRAKE-SHIFT INTERLOCK - COLUMN-SHIFT TRANSMISSION
This vehicle is equipped with a park/brake-shift interlock feature that
prevents the gearshift lever from being moved from P (Park) when the
ignition is in the on position unless the brake pedal is pressed.
If you cannot move the gearshift lever out of P (Park) with ignition in
the on position and the brake pedal pressed, it is possible that a fuse has
blown or the vehicle's brake lamps are not operating properly. Refer to
Fuses and relays in the Roadside Emergencies chapter.
If the fuse is not blown, perform the following procedure:
Note: The following procedure is easier to perform when the steering
column is adjusted to the full up position. Refer to Tilt steering wheel in
the Driver Controls chapter.
1. Apply the parking brake, turn the ignition to the off position, then
remove the key.
2. Move the shift lever boot by
pressing on the edges and moving it
up the gearshift lever.
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