Abstract: Methods and apparatus are provided for one or more electronic keys to be trained to activate multiple vehicles. The apparatus comprises wirelessly communicating electronic key and vehicle authentication modules, each of which comprises inter-coupled processor, non-volatile memory, transmitter and receiver. The module transmitters communicate with the key receiver and vice versa. The key and module exchange ID information during a learning process. These learned IDs are stored in their memories. The key memory stores ID information on a single key and multiple vehicles and the module memory stores ID information on a single vehicle and multiple keys. During authentication, the module and key transmit at least their own IDs to the other. Each compares the received ID to the learned IDs. If they match, authentication is granted and the key command is processed by the vehicle. The number of authenticating keys and vehicles is limited only by onboard memory capacity.

Abstract: Methods and apparatus are provided for rendering electronic keys left behind in a vehicle temporarily inactive. The apparatus comprises a vehicle security control module in wireless communication with the electronic keys, and having operatively coupled together a receiver, a processor, non-volatile memory and a short-range transmitter. When the module receives a valid lock command from any source it sends a short-range interrogation signal to keys within the vehicle. Left-behind keys respond and send their unique ID(s) to the module's receiver. The processor obtains the unique ID(s) from the receiver and sets one or more inhibit flags in memory or equivalent to identify those keys as left-behind keys. The processor thereafter ignores commands from such left-behind keys, thereby rendering them temporarily inoperative until a valid unlock command is received form another source, whereupon the processor clears the inhibit flags from memory and restores the left-behind keys to active status.

Abstract: Methods and apparatus are provided for determining the duration a motor vehicle engine may operate while operator authorization is verified in response to an ignition request. In one embodiment the method includes the steps of decrementing a pre-authorization timer from a first predetermined time limit and a maximum authorization timer from a second predetermined time limit in response to the ignition request. Also upon receipt of the ignition request an authorization process is initiated. Decrementing of the pre-authorization timer is halted in response to active operation of the starter motor of the motor vehicle, and operation of the motor vehicle is inhibited if either the pre-authorization timer or the maximum authorization timer decrements to zero before completion of the authorization operation.

Abstract: Methods and apparatus are provided for insuring that a motor vehicle is being operated by an authorized operator. The apparatus includes an electronic control unit (ECU), an engine immobilizer unit, and a shared encryption key. The ECU generates a challenge by combining the output of a pseudo-random number generator and the output of a somewhat random number generator and cycling the combined number through a linear feedback shift register. The ECU sends the challenge to the immobilizer unit where it is encrypted with the shared key and sent back to the ECU as a response. The ECU uses the same key to encrypt the challenge and compares the encrypted challenge to the response. If the response matches the encrypted challenge, engine operation is enabled.

Abstract: Methods and system are provided for an adaptive vehicle locking system. The system includes a plurality of vehicle door locks, each configured to lock and unlock in response to a first signal, a plurality of sensors each configured to sense opening and closing of an associated vehicle door and to send second signals in response to opening and closing of the associated vehicle door, and a lock requester configured to send a third signal. A control module that includes a memory for storing a history of the second signals and a timer adaptively settable in response to the history of the second signals is configured to receive the second signals from the plurality of sensors and the third signal from the lock requester. The control module is also configured to send a first signal to the plurality of vehicle door locks causing the vehicle door locks to lock in response to timing out of the timer following receipt of the third signal.