Abstract:
Disclosed is an electronic control apparatus for a vehicle which includes: 1) first storage means for storing vehicle identification information unique to the vehicle; 2) second storage means for storing immobilizer identification information unique to the vehicle; 3) command receiving means for receiving, from an external control apparatus, an update command that commands the electronic control apparatus to update the vehicle identification information stored in the first storage means; and 4) information handling means for handling all the information stored in the first and second storage means. Moreover, in the electronic control apparatus, upon receipt of the update command by the command receiving means, the information handling means updates the immobilizer identification information stored in the second storage means as well as the vehicle identification information stored in the first storage means.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is based on and claims priority from Japanese Patent Application No. 2008-112628, filed on Apr. 23, 2008, the content of which is hereby incorporated by reference in its entirety into this application. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Technical Field of the Invention 
         [0003]    The present invention relates to an electronic control apparatus for vehicles which updates, upon being transferred from one vehicle to another, vehicle identification information stored in the apparatus. 
         [0004]    2. Description of the Related Art 
         [0005]    Conventionally, for example as disclosed in Japanese Patent First Publication No. 2001-301572, an engine ECU (Electronic Control Unit) for a motor vehicle has a VIN (Vehicle Identification Number) stored in a memory (e.g., an EEPROM) thereof; the VIN is unique to the vehicle. 
         [0006]    Moreover, in addition to the VIN, the engine ECU also has stored in the memory thereof immobilizer identification information, various types of diagnostic information, and learning values for control of the vehicle. Here, the immobilizer identification information denotes information which is unique to the vehicle or a valid user (or users) of the vehicle and is used to identify whether a user intending to activate the vehicle is the valid user. 
         [0007]    More specifically, upon detection of immobilizer identification information from a portable device (e.g., an ignition key) of the user intending to activate the vehicle, the engine ECU or an immobilizer ECU of the vehicle crosschecks the detected immobilizer identification information against the immobilizer identification information stored in the memory. When the detected identification information coincides or matches with the immobilizer identification information stored in the memory, the engine ECU or the immobilize ECU identifies the user intending to activate the vehicle as the valid user and allows the identified user to activate the engine of the vehicle. 
         [0008]    Furthermore, when the engine ECU is removed from the vehicle and installed to a new vehicle, it is necessary to update the VIN stored in the memory with the VIN of the new vehicle. This is because without updating the VIN stored in the memory of the engine ECU, the new vehicle cannot pass the motor vehicle inspection conducted by the government. 
         [0009]    In addition, future OBD-related regulations will probably stipulate that all emission-related diagnostic information stored in the engine ECU be erased when updating the VIN stored in the memory of the engine ECU. Here, OBD stands for On-Board Diagnostics. 
         [0010]    Moreover, it is preferable that other information stored in the engine ECU than the VIN and emission-related information be updated along with the VIN. It is further preferable to minimize the man-hours needed to update the information other than the VIN and emission-related information. 
       SUMMARY OF THE INVENTION 
       [0011]    The present invention has been made in view of the above-mentioned problems. 
         [0012]    The inventors of the present invention have focused their attention on the immobilizer identification information as the information to be preferably updated along with the VIN. This is because when the immobilizer identification information stored in the engine ECU is not updated and thus different from the immobilizer identification information of the new vehicle, the valid user of the new vehicle may be unable to activate the new vehicle. Accordingly, the inventors have come to consider that when updating the VIN, it is preferable to update the immobilizer identification information stored in the engine ECU with that of the new vehicle. 
         [0013]    According to the present invention, there is provided an electronic control apparatus for a vehicle. The apparatus includes: 1) first storage means for storing vehicle identification information unique to the vehicle; 2) second storage means for storing immobilizer identification information unique to the vehicle; 3) command receiving means for receiving, from an external control apparatus, an update command that commands the electronic control apparatus to update the vehicle identification information stored in the first storage means; and 4) information handling means for handling all the information stored in the first and second storage means. Moreover, in the apparatus, upon receipt of the update command by the command receiving means, the information handling means updates the immobilizer identification information stored in the second storage means as well as the vehicle identification information stored in the first storage means. 
         [0014]    With the above configuration, the apparatus can update both the vehicle identification information stored in the first storage means and the immobilizer identification information stored in the second storage means only upon receipt of the single update command. Consequently, compared to the case of updating the vehicle identification information and immobilizer identification information by issuing two separate update commands, the necessary man-hours can be reduced. 
         [0015]    Preferably, in the electronic control apparatus, upon receipt of the update command by the command receiving means, the information handling means performs a single information handling process to update both the vehicle identification information stored in the first storage means and the immobilizer identification information stored in the second storage means. 
         [0016]    With the above configuration, the necessary man-hours for updating both the vehicle identification information and the immobilizer identification information can be further reduced in comparison of the case of updating them by performing two separate updating processes. 
         [0017]    Preferably, the electronic control apparatus further includes information acquiring means for acquiring immobilizer identification information from another electronic control apparatus that is installed in the same vehicle as the electronic control apparatus. The information handling means updates the immobilizer identification information stored in the second storage means with the immobilizer identification information acquired by the information acquiring means. 
         [0018]    Preferably, the electronic control apparatus further includes third storage means for storing learning values for control of the vehicle. In the information handling process, the information handling means further initializes the learning values stored in the third storage means to default values. 
         [0019]    Preferably, upon receipt of the update command by the command receiving means, the information handling means automatically performs the information handling process without communicating with the external control apparatus. Alternatively, the information handling means may automatically perform, while communicating with the external control apparatus, the information handling process without any human intervention. 
         [0020]    Preferably, in the information handling process, the information handling means first updates the vehicle identification information stored in the first storage means and then updates the immobilizer identification information stored in the second storage means. When it fails to successfully update the vehicle identification information stored in the first storage means, the information handling means refrains from further updating the immobilizer identification information stored in the second storage means. 
         [0021]    Preferably, the electronic control apparatus further includes fourth storage means for storing emission-related diagnostic information on the vehicle. In the information handling process, the information handling means further erases the emission-related diagnostic information from the fourth storage means. 
         [0022]    The electronic control apparatus may be an ECU (Electronic Control Unit) for controlling an engine of the vehicle. 
         [0023]    The vehicle identification information may be a vehicle identification number of the vehicle. 
         [0024]    The first and second storage means may be made up of a common nonvolatile memory. Further, the nonvolatile memory may be an EEPROM. 
         [0025]    The electronic control apparatus may also be so configured that: upon receipt of the update command by the command receiving means, the information handling means performs a first update process to update the vehicle identification information stored in the first storage means; and upon completion of the first update process, the information handling means performs a second update process to update the immobilizer identification information stored in the second storage means. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    The present invention will be understood more fully from the detailed description given hereinafter and from the accompanying drawings of one preferred embodiment of the invention, which, however, should not be taken to limit the invention to the specific embodiment but are for the purpose of explanation and understanding only. 
           [0027]    In the accompanying drawings: 
           [0028]      FIG. 1  is a functional block diagram showing a vehicle control system according to the preferred embodiment of the invention; 
           [0029]      FIG. 2  is a schematic view illustrating the transfer of an engine ECU according to the preferred embodiment from one vehicle to another; and 
           [0030]      FIG. 3  is a flow chart illustrating an information handling process of the engine ECU according to the preferred embodiment. 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENT 
       [0031]      FIG. 1  shows a vehicle control system according to a preferred embodiment of the invention. 
         [0032]    As shown in  FIG. 1 , the vehicle control system includes an engine ECU  10  and an immobilizer ECU  60 , which communicate with each other via an on-board network, for example a CAN (Controller Area Network). 
         [0033]    The engine ECU  10  is designed to control the engine of the vehicle to operate in a desired operating condition. The engine ECU  10  is configured with, for example, input and output circuits, a microcomputer and its peripheral circuits, input and output terminals, a case or housing, and holding members. The engine ECU  10  is installed, for example, in the passenger compartment or engine compartment of the vehicle. 
         [0034]    Functionally, the engine ECU  10  includes a processing block  12 , an operating condition detection block  14 , a control signal output block  16 , a RAM  20 , a SRAM  22 , an EEPROM  24 , and an indicator control block  30 . 
         [0035]    The processing block  12  is configured with hardware which includes a CPU, a timer, and a ROM. To control the engine to operate in a desired operating condition, the processing block  12  first computes the values of various parameters based on the output signals of various sensors which are provided by the operating condition detection block  14 ; then, based on the computed values of the parameters, the processing block  12  controls various actuators through the control signal output block  16 . Moreover, the processing block  12  also performs a self-diagnosis function to detect malfunctions of components of the vehicle. 
         [0036]    The operating condition detection block  14  receives the output signals of the various sensors which together represent the current operating condition of the engine. The output signals may include, for example, an accelerator position signal (indicated by ACCP in  FIG. 1 ) output from an accelerator position sensor, an engine speed signal (indicated by Ne in  FIG. 1 ) output from an engine speed sensor, a cooling water temperature signal (indicated by Tw in  FIG. 1 ) output from a water temperature sensor, an oxygen concentration signal (indicated by O 2  in  FIG. 1 ) output from an oxygen sensor, an intake air flow signal (indicated by V in  FIG. 1 ) output from an intake air flow sensor, and an ignition signal (indicated by IGN in  FIG. 1 ) output from an ignition switch. 
         [0037]    The control signal output block  16  outputs control signals provided by the processing block  12  to the various actuators, causing the actuators to operate in accordance with the control signals to make the engine operate in a desired operating condition. The actuators may include, for example, ignition plugs and fuel injectors. 
         [0038]    The RAM  20  temporarily stores the results of computation by the processing block  12 . The SRAM (Standby RAM)  22  is a volatile memory that is always supplied with electric power by a battery of the vehicle even when the ignition switch is turned off. In this sense, the SRAM  22  is also referred to as power-backed up RAM. The EEPROM  24  is an Electrically Erasable Programmable Read-Only Memory. 
         [0039]    For example, upon detection of malfunctions of emission-related components of the vehicle, the processing block  12  first stores DTCs (Diagnostic Trouble Codes) indicative of the detected malfunctions into the SRAM  22 . Then, among the DTCs indicative of the detected malfunctions, the processing block  12  selects those which are identical to predetermined DTCs and stores the selected DTCs into the EEPROM  24  as PDTCs (Permanent DTCs) during the ignition cycle (i.e., the time period from the turning on to the turning off of the ignition switch or the time period from the turning on to the next turning on of the ignition switch). Here, the emission-related components of the vehicle may include sensors necessary for emission control of the engine, such as the water temperature sensor for sensing the temperature of cooling water of the engine and the intake air flow sensor for sensing the flow of intake air into the engine. In addition, the California Air Resources Board (CARB) proposes that DTCs indicative of detected malfunctions of components of vehicles be stored as PDTCs into nonvolatile memories such as an EEPROM. 
         [0040]    The EEPROM  24  stores a VIN (Vehicle Identification Number) unique to the vehicle, an immobilizer ID unique to the vehicle or a valid user (or users) of the vehicle, and learning values for control of the vehicle. The learning values stored in the EEPROM  24  may include, for example, those for learning the performance characteristics of the fuel injectors and throttle valve of the engine. In addition, it is stipulated by regulations that the VIN be stored in a nonvolatile memory. 
         [0041]    As above, in the engine ECU  10  according to the present embodiment, the EEPROM  24  functions as means for storing vehicle identification information unique to the vehicle, immobilizer identification information unique to the vehicle or the valid user (or users) of the vehicle, and the learning values for control of the vehicle. Moreover, both the SRAM  22  and the EEPROM  24  function as means for storing diagnostic information. 
         [0042]    The indicator control block  30  controls the Malfunction Indicator Lamp (MIL)  40  to indicate the detected malfunctions of the components of the vehicle. 
         [0043]    An external computer  50  is, as an external control apparatus, connected to the engine ECU  10  via an input/output interface (not shown). The external computer  50  reads the various types of information stored in the SRAM  22  and EEPROM  24  by communicating with the engine ECU  10 . Moreover, the external computer  50  commands the engine ECU  10  to update the various types of information stored in the SRAM  22  and EEPROM  24 . 
         [0044]    The immobilizer ECU  60  has almost the same configuration as the engine ECU  10 . Therefore, identical blocks having substantially identical functions in the engine ECU  10  and immobilizer ECU  60  are assigned to the same reference numerals. 
         [0045]    Functionally, the immobilizer ECU  60  includes an ID detection block  62  that detects an immobilizer ID from an ignition key of a user intending to activate the vehicle. On the other hand, the EEPROM  24  of the immobilizer ECU  60  has an immobilizer ID stored therein. The processing block  12  of the immobilizer ECU  60  checks whether the immobilizer ID detected by the ID detection block  62  is identical to the immobilizer ID stored in the EEPROM  24  of the immobilizer ECU  60 . When the two IDs are identical to each other, the processing block  12  identifies the user intending to activate the vehicle as the valid user of the vehicle; otherwise, the processing block  12  identifies the user as an invalid user. After identifying the user, the processing block  12  encodes the identification results and sends to the engine ECU  10  the encoded identification results along with the immobilizer ID stored in the EEPROM  24  of the immobilizer ECU  60 . 
         [0046]    When the identification results sent from the immobilizer ECU  60  indicates that the user is invalid, the engine ECU  10  does not start the engine. Moreover, when the identification results indicates that the user is valid but the immobilizer ID sent from the immobilizer ECU  60  is different from that stored in the EEPROM  24  of the engine ECU  10 , the engine ECU  10  also does not start the engine. The engine ECU  10  starts the engine only when the identification results indicates that the user is valid and the immobilizer ID sent from the immobilizer ECU  60  is identical to that stored in the EEPROM  24  of the engine ECU  10 . 
         [0047]    In addition, when the user intending to activate the vehicle is identified as invalid, the indicator control block  30  of the immobilizer ECU  60  illuminates a Warning Lamp (WL)  70 . 
         [0048]    After having described the overall configuration of the vehicle control system according to the present embodiment, functions of the engine ECU  10  will be described hereinafter. 
         [0049]    In the present embodiment, the engine ECU  10  performs the functions by executing programs installed in the ROM of the engine ECU  10 . 
       Function of Receiving VIN Update Command  
       [0050]    Referring to  FIG. 2 , when the engine ECU  10  is removed from the vehicle  100  and installed to another vehicle  200 , it is necessary to update the VIN a of the vehicle  100  stored in the EEPROM  24  of the engine ECU  10  with the VIN b of the vehicle  200 . 
         [0051]    To this end, the engine ECU  10  receives, from the external computer  50 , a VIN update command that commands the engine ECU  10  to update the VIN a of the vehicle  100  stored in EEPROM  24  with the VIN b of the vehicle  200 . 
       Function of Acquiring Immobilizer ID  
       [0052]    After receipt of the VIN update command, the engine ECU  10  acquires the immobilizer ID B of the vehicle  200  from the immobilizer ECU  210  of the vehicle  200 . 
         [0053]    More specifically, the engine ECU  10  sends a request signal to the immobilizer ECU  210  of the vehicle  200 ; upon receipt of the request signal, the immobilizer ECU  210  sends the immobilizer ID B of the vehicle  200  to the engine ECU  10 . 
       Function of Handling Information  
       [0054]    The engine ECU  10  first updates the VIN a of the vehicle  100  stored in the EEPROM  24  of the engine ECU  10  with the VIN b of the vehicle  200  sent from the external computer  50 . 
         [0055]    Further, the engine ECU  10  erases the DTCs from the SRAM  22  and PDTCs from the EEPROM  24 . 
         [0056]    Moreover, the engine ECU  10  initializes the learning values stored in the EEPROM  24  to default values which are determined by averaging learning values for different vehicles. In addition, the learning values may also be updated with other predetermined values. 
         [0057]    Furthermore, the engine ECU  10  updates the immobilizer ID A of the vehicle  100  stored in the EEPROM  24  of the engine ECU  10  with the immobilizer ID B of the vehicle  200  acquired from the immobilizer ECU  210  of the vehicle  200 . 
         [0058]    In the present embodiment, upon receipt of the VIN update command sent from the external computer  50 , the engine ECU  10  automatically updates the VIN and immobilizer ID, erases the DTCs and PDTCs, and initializes the learning values without communicating with the external computer  50 . Moreover, when it fails to successfully update the VIN, the engine ECU  10  refrains from further performing the remaining tasks and informs the external computer  50  of the failure in updating the VIN. Consequently, the immobilizer ID and the learning values can be prevented from being updated with or initialized to erroneous values. 
         [0059]      FIG. 3  shows an information handling process of the engine ECU  10  according to the present embodiment. The engine ECU  10  performs this process upon being transferred one vehicle (e.g., the vehicle  100 ) to another (e.g., the vehicle  200 ). 
         [0060]    More specifically, after the transfer of the engine ECU  10  from the vehicle  100  to the vehicle  200 , the external computer  50  sends the VIN update command to the engine ECU  10 ; upon receipt of the VIN update command, the engine ECU  10  starts to perform the information handling process. In addition, the engine ECU  10  may or may not send to the external computer  50  an acknowledge signal for acknowledging safe receipt of the VIN update command. 
         [0061]    First, in step S 300 , the engine ECU  10  updates the VIN a of the vehicle  100  stored in the EEPROM  24  of the engine ECU  10  with the VIN b of the vehicle  200 . 
         [0062]    In addition, in the case of the engine ECU  10  sending the acknowledge signal, the external computer  50  may send the VIN b of the vehicle  200  to the engine ECU  10  upon receipt of the acknowledge signal. Otherwise, the external computer  50  may send the VIN b of the vehicle  200  to the engine ECU  10  together with the VIN update command. 
         [0063]    In step S 302 , the engine ECU  10  checks whether the VIN a of the vehicle  100  has been successfully updated in the EEPROM  24  of the engine ECU  10  with the VIN b of the vehicle  200 . 
         [0064]    If the check in step S 302  results in a “NO” answer, then the process directly goes to the end without further performing the remaining tasks. 
         [0065]    In addition, in this case, the engine ECU  10  may also try again the updating of the VIN a with the VIN b. Moreover, when the updating of the VIN a with the VIN b is still unsuccessful after being tried more than predetermined times, the engine ECU  10  may diagnose the EEPROM  24  as malfunctioning and inform the external computer  50  of the malfunction of the EEPROM  24 . As a result, one may take necessary measures, for example replacing the EEPROM  24  with a new one. 
         [0066]    On the other hand, if the check in step S 302  results in a “YES” answer, then the process proceeds to step S 304 . 
         [0067]    In step S 304 , the engine ECU  10  acquires the immobilizer ID B of the vehicle  200  from the immobilizer ECU  210  of the vehicle  200 , and updates the immobilizer ID A of the vehicle  100  stored in the EEPROM  24  of the engine ECU  10  with the immobilizer ID B. 
         [0068]    In succeeding step S 306 , the engine ECU  10  erases the DTCs from the SRAM  22  and the PDTCs from the EEPROM  24  of the engine ECU  10 , and initializes the Learning Values (L.V.) stored in the EEPROM  24  of the engine ECU  10  to the default values. After that, the process goes to the end. 
         [0069]    The above-described engine ECU  10  according to the present embodiment has the following advantages. 
         [0070]    In the present embodiment, upon receipt of the VIN update command from the external computer  50 , the engine ECU  10  updates the immobilizer ID A of the vehicle  100  stored in the EEPROM  24  with the immobilizer ID B of the vehicle  200  as well as updates the VIN a of the vehicle  100  stored in the EEPROM  24  with the VIN b of the vehicle  200 . In other words, the engine ECU  10  updates both the VIN a and immobilizer ID A of the vehicle  100  stored in the EEPROM  24  of the engine ECU  10  only upon receipt of the single VIN update command from the external computer  50 . 
         [0071]    Consequently, compared to the case of updating the VIN a and immobilizer ID A of the vehicle  100  with the VIN b and immobilizer ID B of the vehicle  200  by issuing two separate update commands by the external computer  50 , the man-hours needed to update them can be reduced. 
         [0072]    Moreover, in the present embodiment, upon receipt of the VIN update command from the external computer  50 , the engine ECU  10  performs the single information handling process to both update the VIN a of the vehicle  100  stored in the EEPROM  24  with the VIN b of the vehicle  200  and update the immobilizer ID A of the vehicle  100  stored in the EEPROM  24  with the immobilizer ID B of the vehicle  200 . 
         [0073]    Consequently, compared to the case of updating the VIN a and immobilizer ID A of the vehicle  100  with the VIN b and immobilizer ID B of the vehicle  200  by performing two separate update processes, the manhours needed to update them can be further reduced. 
         [0074]    In the present embodiment, the engine ECU  10  acquires the immobilizer ID B of the vehicle  200  from the immobilizer ECU  210  that is installed in the same vehicle  200  as the engine ECU  10 . 
         [0075]    Consequently, the engine ECU  10  can easily and reliably acquire the immobilizer ID B of the vehicle  200 . 
         [0076]    In the present embodiment, the engine ECU  10  initializes, in the information handling process, the learning values stored in the EEPROM  24  to default values which are determined by averaging learning values for different vehicles. 
         [0077]    Consequently, compared to the case of not initializing the learning values, it is possible to reduce the time required to obtain learning values suitable for control of the vehicle  200 . 
         [0078]    In the present embodiment, upon receipt of the VIN update command from the external computer  50 , the engine ECU  10  automatically performs the information handling process without communicating with the external computer  50 . 
         [0079]    Consequently, the engine ECU  10  can speedily handle all the information stored therein. 
         [0080]    In the present embodiment, when it fails to successfully update the VIN a of the vehicle  100  in the EEPROM  24  with the VIN b of the vehicle  200 , the engine ECU  10  refrains from further updating the immobilizer ID a of the vehicle  100  with the immobilizer ID B of the vehicle  200  and initializing the learning values to the default values. 
         [0081]    Consequently, the immobilizer ID a of the vehicle  100  and the learning values can be prevented from being updated with or initialized to erroneous values. 
         [0082]    In the present embodiment, the engine ECU  10  erases, in the information handling process, the DTCs from the SRAM  22  and the PDTCs from the EEPROM  24 . 
         [0083]    Consequently, compared to the case of performing the tasks of updating the VIN a of the vehicle  100  and erasing the DTCs and PDTCs by performing two different processes, the man-hours needed to complete the tasks can be reduced. 
         [0084]    While the above particular embodiment of the invention has been shown and described, it will be understood by those skilled in the art that various modifications, changes, and improvements may be made without departing from the spirit of the invention. 
         [0085]    For example, in the previous embodiment, the engine ECU  10  automatically performs the information handling process without communicating with the external computer  50 . 
         [0086]    However, the engine ECU  10  may also automatically perform the information handling process, while communicating with the external computer  50 , without any human intervention. In this case, it is still possible for the engine ECU  10  to speedily handle all the information stored therein. 
         [0087]    Moreover, in the previous embodiment, in the information handling process, the engine ECU  10  updates the VIN and immobilizer ID, erases the DTCs and PDTCs, and initializes the learning values for control of the vehicle  100  to the default values. 
         [0088]    However, in addition to the above tasks, the engine ECU  10  may further update, erase, or initialize other information unique to the vehicle  100  in the information handling process. 
         [0089]    In the previous embodiment, the immobilizer ID and learning values are stored in the same memory (i.e., the EEPROM  24 ) as the VIN. 
         [0090]    However, the immobilizer ID and learning values may also be stored in a different memory from the VIN. For example, the engine ECU  10  may be further equipped with an auxiliary power source, and the SRAM  22  may be powered by the auxiliary power source when the engine ECU  10  is removed from the vehicle  100 . In this case, the immobilizer ID and learning values may be stored in the SRAM  22  instead of the EEPROM  24 . 
         [0091]    In the previous embodiment, the engine ECU  10  acquires the immobilizer ID B of the vehicle  200  from the immobilizer ECU  210  of the vehicle  200 . 
         [0092]    However, it is also possible for the engine ECU  10  to acquire the immobilizer ID B of the vehicle  200  from any other ECU of the vehicle  200  which has the immobilizer ID B stored therein. Further, it is also possible for the engine ECU  10  to acquire the immobilizer ID B of the vehicle  200  from a portable device (e.g., an ignition key) of a valid user of the vehicle  200 . 
         [0093]    In the previous embodiment, in step S 304  of the information handling process, the engine ECU  10  acquires the immobilizer ID B of the vehicle  200  from the immobilizer ECU  210  of the vehicle  200 , and updates the immobilizer ID A of the vehicle  100  in the EEPROM  24  of the engine ECU  10  with the immobilizer ID B. 
         [0094]    However, in step S 304  of the information handling process, the engine ECU  10  may initialize the immobilizer ID A of the vehicle  100  in the EEPROM  24  to a default immobilizer ID without acquiring the immobilizer ID B of the vehicle  200  from the immobilizer ECU  210 . Instead, at the start of the next ignition cycle, the engine ECU  10  may send a request signal to the immobilizer ECU  210 , receive the immobilizer ID B of the vehicle  200  which is sent by the immobilizer ECU  210  in response to receipt of the request signal, and update the default immobilizer ID in the EEPROM  24  with the received immobilizer ID B. 
         [0095]    In the previous embodiment, the functions of the engine ECU  10  are performed by executing the programs installed in the ROM of the engine ECU  10 . 
         [0096]    However, it is also possible to perform at least one of the functions of the engine ECU  10  by hardware means, for example a dedicated electrical circuit. 
         [0097]    In the previous embodiment, upon receipt of the VIN update command from the external computer  50 , the engine ECU  10  performs the single information handling process to both update the VIN a of the vehicle  100  stored in the EEPROM  24  with the VIN b of the vehicle  200  and update the immobilizer ID A of the vehicle  100  stored in the EEPROM  24  with the immobilizer ID B of the vehicle  200 . 
         [0098]    However, the engine ECU  10  may also be so configured that: upon receipt of the VIN update command from the external computer  50 , the engine ECU  10  performs the information handing process to only update the VIN a of the vehicle  100  with the VIN b of the vehicle  200 ; and upon completion of the information handing process, the engine ECU  10  further performs, either consecutively or with a time interval, an update process to update the immobilizer ID A of the vehicle  100  with the immobilizer ID B of the vehicle  200 .