Use of Standard Passive Anti-Theft System (PATS) Keys

When using a standard (non-IKT) PATS key to start the vehicle, an IKT key (from another vehicle) on the same key ring may possibly be programmed into the vehicle for remote entry functionality, resulting in the IKT key being able to operate the lock and unlock functions of the vehicle (but the IKT key cannot start the vehicle). This should not cause a PATS no-start of either the first or the second vehicle, but the IKT key may be able to operate the lock and unlock functions of both vehicles. The IKT key is able to start the original vehicle to which it is programmed and does start the second vehicle. At this time, it is necessary to carry out an Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment procedure and then to make certain the IKT key for the second vehicle is removed from the key ring in order to prevent this concern from occurring again. Also, if an IKT key is used to start the vehicle, the vehicle only reads the IKT key in the ignition lock cylinder and does not read the second IKT on the key ring. Using an IKT key to start both vehicles, rather than standard PATS keys, prevents the second IKT (transmitter portion only) from being programmed into the first vehicle.