METHOD OF CHANGING DATA IN READ-ONLY MEMORY OF ENGINE CONTROL UNIT OF AUTOMOBILE SECURITY SYSTEM Russian patent published in 2006 - IPC B60R25/04 

FIELD: transport engineering.

SUBSTANCE: invention relates to means of prevention of unauthorized use of automobile engine. Proposed security system includes immobilizer and engine control unit, each furnished with microprocessor, work memory and read-only memory. In process of implementing the method, diagnostic instrument is coupled with engine control unit and access to data in read-only memory of engine control unit is provided to diagnostic instrument to introduce changes into said data. Peculiarities of proposed method, as distinct from known ones, is that legality of. User to carry out such changes is checked by immobilizer and results of checks done by immobilizer are recorded in work memory of engine control unit. After beginning of engine control unit. After beginning of communication between diagnostic instrument and engine control unit, result of checking of legality of User by immobilizer is read from work memory and access for diagnostic instrument to data in read-only memory is opened only in case when result of checking of legality User is positive.

EFFECT: increased degree of protection of read-only memory of automobile control unit from illegal changes of data.

6 cl, 1 dwg