* Forgotten Code: You'll need to reprogram the keypad with your dealer's help or possibly a locksmith familiar with Ford vehicles. The process involves using the ignition key and following a specific sequence. The owner's manual might have some instructions but often leaves out the full programming procedure.
* Keypad Malfunction: If the keypad isn't responding at all (buttons are stuck, unresponsive, etc.), the keypad itself may be faulty. This will also require professional help – either repair or replacement of the keypad assembly. This is a more involved repair than just resetting a code.
* Programming Issues: If you've recently tried to program the keypad and it's not working correctly, you might need to start the programming process over from the beginning. Again, consult the owner's manual or a professional for the correct steps.
In short: You can't simply "reset" it like a typical electronic device. If you're having trouble with your keypad, you will likely need assistance from a Ford dealer or a qualified automotive locksmith.