FORD 2004 F-150 v.1 - Manual (Page 96)

ignition from 1 (OFF) to 3 (ON) (maintain ignition in 3 (ON) for at least
one second, but no more than ten seconds). This step will program your
new key to a coded key.
6. To program additional new unprogrammed key(s), repeat this
procedure from step 1.
If successful, the new coded key(s) will start the vehicle’s engine and the
theft indicator will illuminate for three seconds and then go out.
If not successful, the new coded key(s) will not start the vehicle’s engine
and the theft indicator will flash on and off and you may repeat steps 1
through 5. If failure repeats, bring your vehicle to your dealership to
have the new spare key(s) programmed.
Locks and Security
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