1st, you have to make sure the registered key you are using is a "master key". Is the key a factory Toyota key? Is it black?
2nd, this vehicle has a maximum number of 4 master and 2 sub keys allowed to be registered to the vehicle. If it is at its maximum a delete procedure must be performed.
Well, I guess 1st should be make sure the chicken is a hen, not a rooster.
2004 4runner just starting to build
83 Hilux SR5 is being sold
94 pickup in a pile of parts