Hello and welcome to Just answer.com, Super mechanic here. About your vehicle.
There is a problem with the "passkey ll " system. The best way to diagnose that would be the "interrogator" tool. Most lock smiths will have that. There are 13 different resistence values in the diodes, (in the key) and most times it is a problem with the ignition switch sending the correct information to the decoder module.
The best thing to do would be to get a lock smith to come and check it. They will normally charge about $65, which is less than the dealer, minus the tow charge. They will pinpoint what part is needed.