Ford 2003 Explorer Owner's Manual page 104

Driving
If you cannot move the gearshift lever out of P (Park) with ignition in
the ON position and the brake pedal depressed:
1. Apply the parking brake, turn ignition key to LOCK, then remove the
key.
2. Insert the key and turn it to OFF. Apply the brake pedal and shift
to N (Neutral).
When the key is in the ignition OFF position, the automatic
transmission shift lever can be moved from the P (Park) position
without the brake pedal depressed. To avoid unwanted vehicle
movement, always set the parking brake.
3. Start the vehicle.
If it is necessary to use the above procedure to move the gearshift lever,
it is possible that a fuse has blown or the vehicle's brakelamps are not
operating properly. Refer to Fuses and relays in the Roadside
emergencies chapter.
Do not drive your vehicle until you verify that the brakelamps
are working.
Always set the parking brake fully and make sure the gearshift is
latched in P (Park). Turn the ignition to the LOCK position and
remove the key whenever you leave your vehicle.
If the parking brake is fully released, but the brake warning lamp
remains illuminated, the brakes may not be working properly.
See your dealer or a qualified service technician.
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