Vehicle control network integrated theft deterrent system

1. A vehicle theft deterrent system comprising:

an engine having operating variables;

a sensor package associated with the engine for measuring the engine operating variables;

an engine controller for controlling output of the engine and coupled to the sensor package for receiving measurement readings of the engine operating variables;

an engine ignition system including a key switch relay and a cab ignition relay;

a combination entry system for the entry of enabling codes;

a vehicle body computer connected to the combination entry system to receive enabling codes and operable thereon for checking the validity of entered enabling codes;

an ignition interrupt relay between the key switch relay and the cab ignition relay under the control of the vehicle body computer;

a communication link coupling the vehicle body computer and the engine controller allowing exchange of data between the engine controller and the engine controller including messages for operation on by the engine controller to limit engine output to prevent normal operation of the vehicle; and

the vehicle body computer being responsive to entry of an invalid enabling code through the combination entry system for incapacitating the engine.

2. A vehicle theft deterrent system in accord with claim 1 , further comprising;

the vehicle body computer being responsive to the entry of an invalid enabling code for issuing messages over the communication link directing limiting of engine output by the engine controller.

3. A vehicle theft deterrent system in accord with claim 1 , further comprising:

the vehicle body computer being responsive to the entry of an invalid enabling code for opening the ignition interrupt relay.

4. A vehicle theft deterrent system in accord with claim 1 , further comprising:

the data processing system providing for reducing engine output and opening the ignition interrupt relay in response to determination of invalidity of the vehicle operator identification related data.

5. A vehicle theft deterrent system in accord with claim 4 , further comprising:

a park brake position sensor connected to the vehicle body computer, the vehicle body computer being responsive to the park brake position and engine status for initiating an validation of entered enabling codes.

6. A vehicle theft deterrent system in accord with claim 5 , further comprising:

means responsive to direction from the body computer for signaling to an operator validity and invalidity of entered enabling codes, treating absence of entry of an enabling code as an invalid enabling code.

7. A vehicle theft deterrent system in accord with claim 6 , wherein the communication link is a controller area network.

8. A vehicle theft deterrent system in accord with claim 7 , further comprising:

vehicle speed sensing meas coupled to the communication link for providing vehicle speed information thereon; and

the vehicle body computer being further responsive to vehicle speed exceeding a predetermined minimum for triggering monitoring for entry of an enabling code.

9. An engine ignition system control system comprising:

a key actuated ignition relay system;

an ignition interrupt relay having a control input and disposed connected to the key actuated ignition relay system for interrupting the output of the key actuated ignition relay system;

an engine controller for setting engine output;

a vehicle operator identification system responsive operation of a vehicle system for operation, the vehicle operator identification system providing data related to a vehicle operator's identification;

a data processing system connected to receive the vehicle operator identification related data, and responsive to receipt thereof for determining validity of the same and connected to the control input of the ignition interrupt relay and to the engine controller;

the data processing system being responsive to determination of invalidity of the vehicle operator identification related data for selectively crippling operation of the vehicle;

the data processing system providing for reducing engine output and opening the ignition interrupt relay in response to determination of invalidity of the vehicle operator identification related data; and

the data processing system being responsive to determination of invalid vehicle operator identification related data, or the absence of any such data, to first direct opening of the ignition interrupt relay and second, responsive to failure of opening of the ignition interrupt relay, to direct reduced output from the engine.

10. An engine ignition system control system comprising:

a key actuated ignition relay system;

an ignition interrupt relay having a control input and disposed connected to the key actuated ignition relay system for interrupting the output of the key actuated ignition relay system;

an engine controller for selling engine output;

a vehicle operator identification system responsive operation of a vehicle system for operation, the vehicle operator identification system providing data related to a vehicle operator's identification;

a data processing system connected to receive the vehicle operator identification related data, and responsive to receipt thereof for determining validity of the same and connected to the control input of the ignition interrupt relay and to the engine controller;

the data processing system bein responsive to determination of invalidity of the vehicle operator identification related data for selectively crippling operation of the vehicle;

the data processing system providing for reducing engine output and opening the ignition interrupt relay in response to determination of invalidity of the vehicle operator identification related data; and

the data processing system being responsive to release of a parking brake or operation of the vehicle at a minimum predetermined speed for triggering requirement of acquiring vehicle operator identification data.