Abstract: An authorization checking system for motor vehicles, in which a control unit in the motor vehicle, having a portable user-transponder, in an inquiry-response dialog using data exchange, checks, and allows or blocks, the authorization for unlocking or locking the vehicle doors as well as for starting or driving. In order to be able to modify the identifiers of user-transponders and components of the motor vehicle in a security-relevant manner, a so-called master-transponder is provided in addition to one or a plurality of user-transponders. The master-transponder has a particular, vehicle-specific identifier, using which, in a special-inquiry-response dialog, the authorization to carry out and complete special functions within a preselected scope, going beyond the access and start/drive authorization, can be checked, and allowed or blocked. For carrying out the special functions, the master-transponder has acoustical and/or optical display devices and/or input devices.

Abstract: A vehicle security arrangement includes at least one functional control unit, which provides a first code word; a theft protection control unit, which is coupled via a bus to the at least one functional control unit; and at least one input unit, which transmits to the theft protection control unit a second code word which the theft protection control unit forwards to the at least one function control unit. The theft protection control unit may initiate the provision of the first code word and the second code word. In the at least one functional control unit, a comparison of the first code word of the at least one functional control unit with the second code word takes place. In case of agreement between the first code word and the second code word, the at least one functional control unit enables itself.

Abstract: A method and a device for exchanging data in messages between at least two stations connected via a bus system, the messages containing the data being transmitted by the stations over the bus system and the messages being controlled over time by a first station in such a manner that the first station repeatedly transmits a reference message over the bus at at least one specifiable time interval and the time interval is divided into time windows of specifiable length, the messages being transmitted in the time windows, a reference message and the subsequent time windows until the next reference message being combined into a first cycle, and the first station interrupting the transmission at the end of a first cycle due to a stop request, in particular, a message of the at least second station.

Abstract: The invention relates to a control system for a motor vehicle having a remote control unit or transponder for transmitting information to a receiver housed in the motor vehicle, in which the remote control unit or transponder has a battery or a storage cell. The user is continuously informed concerning the charge condition of the battery or storage cell, if it is provided that the remote control unit or transponder has a monitoring unit for the charge condition of the battery or storage cell and that, using a separate control command, a charge condition identifier can be transmitted, which is displayed in the motor vehicle and which, there, identifies the charge condition of the battery or storage cell of the remote control unit or transponder.

Abstract: The invention relates to a structural theft protection system for motor vehicles with a blocking control device (30) for releasing a motor control device (31), a code acquisition device (20, 21) that is connected to the blocking control device, and a device (32) connected to the blocking control device (30) for acquiring a vehicle use parameter (T, S), as well as with several locally fixed code takeover/output stations (10, 11), wherein the blocking control device (30) keeps the motor control device (31) in the release position only if the blocking control device (30) is fed a new release information by one of the locally fixed code takeover/output stations (10, 11), preferably at regular intervals.

Abstract: A method for the exchange of data in messages between at least two users which are connected by a bus system, the messages containing the data being transmitted by the users via the bus system, and each user containing a predefinable and/or ascertainable timing mark; a first user, in a function as timer, controls the messages as a function of time in such a way that it repeatedly transmits a reference message, which contains time information of the first user, via the bus at a specifiable time interval, and if the timing mark of the second user is reached without a reference message of the first user reaching the second user, the at least second user takes over the function of timer by transmitting its own reference message with its own time information via the bus system.

Abstract: A method and device for the exchange of data in messages between at least two users which are connected by a bus system and have separate time bases, the messages containing the data being transmitted by the users via the bus system; and a first user, in a function as timer, controls the messages as a function of time in such a way that it repeatedly transmits a reference message, which contains time information regarding the time base of the first user, via the bus at a specifiable time interval; the at least second user forms its own time information, using its time base, as a function of the time information of the first user; a correction value is ascertained from the two pieces of time information; and the second user adapts its time information and/or its time base as a function of the correction value.

Abstract: A method for preventing misuse of a transponder left inside a vehicle, which is part of a keyless vehicle access system and coacts with a control system for access and driving authorization located in the vehicle. The control system emits, in response to a locking command, a check signal by way of which it is ascertained whether transponders are still located in the vehicle interior after locking. Transponders which are detected as being located in the vehicle interior after locking are recorded in a memory associated with the control system. Upon a subsequent legitimate access to the vehicle, transponders that are not again detected in the interior are inhibited.

Abstract: To provide a suitable number of display fields (e.g. ARRIVAL; TIME; etc.), each of which characterizes and identifies the significance or import or meaning of a displayed numerical value on a display device (16), the display fields are associated in groups or sets (11-15; 42-45) having a particular geometric position (columns; segmental), and a plurality of keys (21-25) are provided with each key being associated with a group or set of the display fields, and connected to a counter (61) to select a particular one of the display fields within the group or set by the number of key operations, the numerical value associated with the display field then being displayed on the numerical display (16).