How to program your 1999, 2000, 2001, and 2002 Mercury Villager remote keyless entry fob alarm by yourself at home without going to the dealer.
There is even a video below that will show you how this is done!

Enter vehicle, close and lock all doors.
Slowly insert and remove key from ignition 6 times within 10 seconds.
The tail lamps will flash to indicate original code has been erased.
Turn ignition to the ACC position.
Press any button on 1st transmitter.
Hazard lamps will flash to confirm programming.
To enter additional transmitters, unlock then lock the doors using the power lock switch located on the driver door.
Press any buttonon additional transmitter (up to 4 transmitters total possible).
Hazard lamps will flash toconfirm programming.
Open the driver’s door.
Turn ignition off.