Method and safety for a displacement device on a motor vehicle

A method for safeguarding an adjusting device of a motor vehicle wherein controlling a lock of the motor vehicle in the blocking state comprises:

• evaluating the functional reliability of a central control device and its signal links;
• evaluating characteristic values characterizing the operating state of the motor vehicle;
• switching a potential for controlling the lock to an electrical lead connection independent of the signal links;
• transferring a control command through one of the signal links of the central control device to a control device;
• and
• energizing an electromechanical unit of the lock through a power switch of the control device by means of the potential when a fault-free functioning method of the devices and signal connection is detected through evaluation.

A method for safeguarding a locking device of a motor vehicle by preventing an unintended control of a lock of the motor vehicle into the blocking state in the event of a failure, breakdown or started emergency operation of a bus system of the motor vehicle;

• comprising the steps:
• detecting the failure or breakdown through a central control device of the motor vehicle and starting an emergency operation, or
• transferring information on a started emergency operation from a control device through the bus system to the central control device,
• switching a control potential to a lead connection which is connected to the control device and is independent of the connections of the bus system, wherein the switching step is performed by the central control device, and wherein in dependence on this control potential a control of the locking device into the blocking state is prevented.