Method for protecting a microcomputer of a control unit against the manipulation of a program and a device for carrying out the method

A method for protecting a microcomputer of a control unit for a motor vehicle against the manipulation of a control program, the control program being at least partially stored in a rewriteable memory of the microcomputer, protection being provided through use of a validation program stored in the microcomputer for detecting an unauthorized manipulation of the control program, the method comprising the steps of:

• classifying the control unit as one of a serial module and an application module, the serial module and the application module each including a hardware identifier, the hardware identifier of the serial module being distinguishable from the hardware identifier of the application module;
• switching the validation program in the application module, when the control unit is classified as the application module, from an activated state to a deactivated state using standard commands;
• and
• switching the validation program in the serial module, when the control unit is classified as the serial module, from an activated state to a deactivated state using special measures.