Abstract: An anti-theft apparatus prevents a delay in engine start caused by an ID legitimacy determination performed by an immobilizer. When an ignition key is operated, a starter motor is immediately energized and an engine control unit and a theft detector are actuated at the same time. Then, when independent running of the engine is detected by a detector, an immobilization determining section determines whether an enable code has been provided from the theft detector. If no enable code is present, then the immobilization determining section issues a halt command to the engine control unit. Thus, as soon as the key is turned to the on-position, the engine is started, thereby preventing a delay in engine start caused by the ID determination performed by the immobilizer.

Abstract: A vehicle anti-theft system in which, only when the ID signal is obtained from a right ignition key and when the vehicle anti-theft function is halted by the failure of an anti-theft circuit or theft detection unit itself, the start-up of the engine is permitted. The system comprises a unit for generating a start-up enable signal in response to a verification signal representing a right ID signal, and an engine control unit for performing the start-up control of the engine in response to the start-up enable signal and disabling the engine in response to a theft signal. The start-up enable signal generating unit generates a start-up enable signal in response to the fault signal. A dummy line for detecting a breakage is wired along various signal lines wired on the substrate of an immobilizer, which, if intentionally broken by an ill-intentioned third party, could cause a fault signal similar to that for the failure of the immobilizer to be outputted from a determination signal output terminal.

Abstract: An engine control device exhibiting a unique vehicle anti-theft function which prevents a vehicle from being stolen when equipped physically on a vehicle in place of an engine control device with vehicle anti-theft function. The antenna unit detection circuit in an ECU 30b' instructs engine ECU 16 to inhibit engine control when it is detected that an antenna unit 29 which should not originally be connected to ECU 30b' has been connected to ECU 30b', that is, the ECU 30b' without anti-theft function is attached to a vehicle to which an ECU 30a with anti-theft function is to be attached.

Abstract: An engine control system in which control of an engine can be performed after there has been a momentary power disconnection of a power supply, such as the vechicle battery, from an engine control unit of an electronic circuit which executes an anti-theft function. A power supply detecting circuit detect a connecting of the power supply to the engine control unit. A further circuit determines on the basis of the vehicle speed and the RPM whether or not the vehicle is running. When a connecting of the power supply to the engine control unit is dectected, a determination is made whether or not the power supply connecting has occured after a preceding momentary power disconnection if the further circuit determines that the vehicle is running. The anit-theft function of the electronic circuit is disable when it is determined that there has been a preceding momentary power desconnection.

Abstract: Ribs 9'a to 9'd provided in a connector 50b on the terminal device side are coincident with grooves 8'a to 8'd provided in a connector 40b on the ECU 30b side, but are not coincident with grooves 8a to 8d provided in a connector 40a in position, size and shape. Even if the connector 40b of the ECU 30b without the immobilizer CPU 13 is attempted to be engaged the connector 50a which should originally be connected to the ECU 30a with the immobilizer CPU 13, it cannot be engaged or right electrical connections between input/output terminals in the ECU 30a and corresponding terminal devices cannot be achieved. Accordingly, the theft of the vehicle by replacing the ECU 30a with the ECU 30b is prevented.

Abstract: A method and apparatus for vehicular data processing which enable quick, efficient input of first serial data entered from an external device and comparison of the first and second data with prestored second serial data. First serial data is repeatedly sent out asynchronously. The prestored second serial data is sent out in response to a request. Storing of the second serial data is performed until distinctive leading pulse of the first serial data is detected, at which time storing of the second serial data is suspended to permit storing of the first serial data in an interrupt mode.

Abstract: A vehicle anti-theft system in which a registration of an ID code of a new key to a vehicle side cannot easily be made by an ill-intentioned third party. Provided are a first memory for storing ID codes of operation keys and a second memory for storing an ID code of an L-key. Of a particular ID code of an inserted key has been registered as an operation key in the first memory, an immobilizer code stored in an immobllizer code memory is sent out to an engine ECU to enable the engine to be started up, and if the registered L-key is inserted, and operation keys are successively inputted, the renewal mode for the ID code is activated to rewrite the ID codes of the previously registered operation keys with ID codes of subsequently inserted operation keys in the first memory.

Abstract: A vehicle anti-theft engine control device enables engine control to be continued even if the data in the memory, wherein an ID code checking result has been stored, incurs "bit change" due to noise or the like, causing the data to change into data prohibiting engine control. The control device comprises a plurality of engine start enable flags for storing information on the enable/disable state of the engine control, enable flag registering means for registering "1" (enable) in all flags in response to a start permit signal, re-registering means for registering again, when "1" has been registered in at least one of the flags, "1" (enable) in all other enable flags, and control enabling means for enabling the engine control in accordance with the registered/reregistered enable flag.

Abstract: A data processing apparatus for a vehicle which permits accurate and reliable registration of a key ID code in a vehicle. ID code detecting means detects an ID code received in succession from outside. The ID code detected previously is registered in the memory 132 for previous ID code; the ID code detected this time is registered in the memory 133 for the present ID code. First comparing means compares the previous ID code with the present ID code and if the two ID codes match, then the ID code is registered as a reference ID code in an EEPROM. Second comparing means compares the present ID code with the reference ID code and if the two ID codes match, then it issues an engine control enable (OK) signal to an engine CPU.

Abstract: A vehicle anti-theft engine control device which is also applicable to an engine control unit without a vehicle anti-theft function and which can be used in combination with any type of vehicle anti-theft function as necessary. The engine control device for vehicle anti-theft function comprises an engine control unit for controlling the start of the engine in response to a start permit signal; an anti-theft function provision determining means for determining whether the engine is equipped with a vehicle anti-theft device or not and for issuing a signal indicating the presence or absence of the anti-theft function; a theft detector means for receiving a signal indicating that legitimate starting operation is being performed and for issuing a validation signal; and means for issuing a start permit signal in response to the validation signal received from the theft detector means or the signal indicating the absence of the anti-theft function.

Abstract: A vehicle antitheft system comprising an ID code compare unit for comparing a key ID code obtained from an ignition key with a reference ID code stored in advance in the vehicle and generating an enable signal when these ID codes are in a preset relationship (for example, both codes are identical), an engine ECU for receiving the enable signal and enabling control of the engine when the enable signal is correct and a delay times that is started in response to generation of the enable signal and generates a signal which enables starting of the motor starter after the lapse of a preset time period following the generation of the enable signal (for example, at least period necessary for the engine ECU to store or identify the enable signal).

Abstract: A pressure sensor based on electrostatic capacity method is disclosed, which comprises the main body of a pressure sensing element having one end surface as a pressured face and the other end surface as a back, for detecting the pressure of a measurement fluid acting on the pressured face, a seal member, a measure pattern on the back, and a one-chip IC. For size reduction, an input-output policy is provided near the main body of the pressure sensing element, and it effects input and output with respect to the pressure sensing element main body while preventing external disturbances and improving the accuracy of measurement.

Abstract: A pressure sensor of electrostatic capacitance type is disclosed, which detects the pressure of a measurement fluid acting on a pressured surface of an elastic diaphragm from a change in the electrostatic capacitance between opposed electrodes provided on opposed surface of a ceramic base and the elastic diaphragm. The base side electrode comprises a plurality of division electrode one enclosing the next inner one. Of these division electrodes the outermost one is grounded or held at a predetermined voltage, or it is covered by overcoat glass, and thus it is imparted with a function of stabilizing the measurement value. In an electrode hole for leading an electrode to the outside, a path is formed for leading atmospheric air or like fluid providing for the reference pressure for pressure measurement into the space defined between the base and elastic diaphragm.