I have a 2004 LC with 3 keys. One is a master key with buttons (confirmed as master via FAQ). The second is a valet key without buttons. Both of these keys do what they are intended to do. I have a third key with buttons. The buttons unlock the doors and the key is cut and kicks the starter over but does not start the truck. This key causes the security light to continually blink, marking it as an unrecognized key. All that is good, so I follow the sequence in the FAQ to program the key, but after all the pedal pressing etc. the light still blinks continuously and the key is not programmed - ie, nothing happens. Any ideas what could be the problem? I think the battery is ok since it unlocks the door remotely.