Method and apparatus for enhanced vehicle protection

• US 5,684,339 A
• Filed: 01/09/1997
• Issued: 11/04/1997
• Est. Priority Date: 01/16/1996
• Status: Expired due to Term

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Treharne, William D.
• Primary Examiner(s): Elms, Richard T.
• Application Number:
  US08/781,077
• Time in Patent Office: 299 Days
• Field of Search: 307/9.1-10.6, 180/287, 70/237, 70/277, 70/228, 70/252, 70/370, 123/198 DB, 123/198 DC, 340/425.5, 340/426, 340/825.3-825.32, 340/825.34, 340/825.44, 340/825.54, 340/825.69, 340/825.72
• US Class Current: 307/10.5
• CPC Class Codes: B60R 25/04 operating on the propulsion system, e.g. engine or drive motor
• CPC Class Codes: B60R 25/24 using electronic identifiers containing a code not memorised by the user

Abstract

A security system for an automotive vehicle having an engine is operatively connected between engine running electrical components that are connected to an electrical power source and a lock switch having at least two operative positions. The security system has a lock switch operator having a memory device carried thereon with a first security code stored in the memory device. A theft control module having a memory storing a second security code is operatively connected between the switch and the engine running electrical devices. The theft control module operates to first permit the engine running electrical components to enable the starting of the engine and then to compare the first and second security codes. Before starting the engine, a counter is compared to a predetermined number so that the engine starting is limited to only a predetermined number of attempts. The engine is disabled if the number of attempts exceeds the predetermined number. If the predetermined number is not exceeded the security codes are checked. Upon finding the first security code not equal to the second security code, the engine running electrical components are disconnected from the electrical power source to disable the engine. The system also may have a feature to allow the electronic engine controller to generate a code and send the code to the theft control module. The theft control module calculates a response based upon a secret algorithm. The electronic engine controller maintains the engine enabled if a code it calculates based on the same secret algorithm is equivalent to the response calculated in the theft control module.

Claims

1. A method for operating a security system for an automotive vehicle having an engine including engine running electrical components and an electronic engine controller, said security system including a theft control module, a lock switch having a selected position providing power to the engine running electrical components, and a key for operating said lock switch and carrying an electronic circuit storing a first security code, wherein said electronic engine controller maintains an attempted start count corresponding to the number of attempts of starting said engine, and wherein said theft control module has a memory storing a second security code, said method comprising the steps of:

placing said key in said lock switch in said selected position;

comparing said attempted start count to a predetermined number;

disabling said engine from starting if said attempted start count exceeds said predetermined number;

starting said engine if said attempted start count does not exceed said predetermined number;

thereafter, comparing said first security code with said second security code; and

if said first security code does not equal said second security code, disconnecting power to said engine running electrical components thereby stopping said engine.