how can i fix my 2002 Ford focus's ignition that is equipt with the P.A.T.S?

i have changed the ignition assembly and cant seem to reprogram the chipt key. ihave tried a few differnt seqwence they dont seem to work. i do have basic scan tools but they dont bring anything up as far as security. what scan tool do i need or is there a nopther method that i may perform?