Abstract:
A diagnostic system for a motor vehicle comprises a component installed within motor vehicle. The system further includes an identifier device mechanically coupled to the component. The identifier device comprises an identifying portion which identifies the component, and the identifier device also comprises a sensor which senses the physical environment in which the identifier device is located. A diagnostic method for a motor vehicle comprises mounting a component within the motor vehicle. The method further includes mechanically coupling an identifier device to the component, the identifier device comprising an identifying portion which identifies the component and the identifier device also including a sensor. The method also comprises confirming, with data provided by the identifying portion, that the identifying portion correctly corresponds to the component. Further, the method includes confirming, with data provided by the sensor, that the identifier device is properly coupled to the component.

Description:
BACKGROUND OF INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to diagnostic systems and methods for motor vehicles.  
           [0003]    2. Background of the Related Art  
           [0004]    In the motor vehicle field, it is known that interchangeable parts are often used, wherein different variants of a component may have the same mounting provisions. While this of course has advantages in terms of cost efficiency, it can also raise an issue. Specifically, where one variant of a part has certain unique functionality not shared by its like-mounted brethren, installing the incorrect part may have adverse consequences on one or more functions of the vehicle.  
           [0005]    This can be an issue in the case of vehicle components which play a role in improving air quality. For example, radiator assemblies for motor vehicles, where the radiator assembly is coated with a catalytic material for converting environmentally harmful substances in ambient air during the utilization of the motor vehicle, are well known. The purpose of this catalytic coating is to utilize the vehicle for improving the environment by cleaning ambient air. Such a coated radiator assembly is likely to have the same mounting provisions as similar radiator assemblies which are not coated and therefore do not have the property of converting the environmentally-harmful substances in ambient air. This is because not all jurisdictions in which a vehicle is sold may require such property, or because some (but not necessarily all) jurisdictions may give exhaust emission “credits” for vehicles with such property. Because a coated radiator will, naturally, cost more than an uncoated one, vehicles built with uncoated radiators will likely be sold in some jurisdictions. Further, uncoated radiators will certainly be made available for aftermarket installation as spare parts in such jurisdictions.  
           [0006]    Where a jurisdiction requires an air-cleaning radiator or gives emission “credits” for such a radiator, the jurisdiction is also likely to require that a diagnostic function be provided to assure that the coated radiator, as opposed to an uncoated radiator without the air-cleaning function, is installed on the vehicle. Assuring with a very high degree of probability that the proper radiator is installed on the vehicle can be very challenging.  
         SUMMARY OF INVENTION  
         [0007]    It is therefore an object of the present invention to provide a diagnostic system and method which can reliably detect whether a proper component is installed in a motor vehicle.  
           [0008]    The present invention provides a diagnostic system for a motor vehicle. The system comprises a component installed within motor vehicle. The system further includes an identifier device mechanically coupled to the component. The identifier device comprises an identifying portion which identifies the component, and the identifier device also comprises a sensor which senses the physical environment in which the identifier device is located.  
           [0009]    The present invention also provides a diagnostic method for a motor vehicle. The method comprises mounting a component within the motor vehicle. The method further includes mechanically coupling an identifier device to the component, the identifier device comprising an identifying portion which identifies the component and the identifier device also including a sensor. The method also comprises confirming, with data provided by the identifying portion, that the identifying portion correctly corresponds to the component. Further, the method includes confirming, with data provided by the sensor, that the identifier device is properly coupled to the component.  
           [0010]    Diagnostic systems and methods according to the present invention are highly advantageous in that they allow, with high reliability, detection that a proper component is installed in a motor vehicle. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0011]    [0011]FIG. 1 is a schematic drawing of an engine  10  and associated cooling system and control componentry, according to one embodiment of the present invention.  
         [0012]    [0012]FIG. 2 illustrates radiator  16  and identifying device  39  of FIG. 1.  
         [0013]    [0013]FIG. 3 illustrates with greater detail identifying device  39  and its interconnection with ECU  42 .  
         [0014]    [0014]FIG. 4 is a graph including the temperature signature near the inlet  36  of radiator  16  when thermostat  20  opens to allow coolant flow into radiator  16 . 
     
    
     DETAILED DESCRIPTION  
       [0015]    Referring to FIG. 1, a schematic of an engine  10  for a motor vehicle in accordance with a preferred embodiment of the present invention is illustrated. In this embodiment, engine  10  is a conventional combustion engine. A cooling circuit  12  is fitted to the engine  10 . The cooling circuit  12  is of a conventional type and comprises cooling channels  14 , a radiator  16 , a coolant pump  18 , and a thermostat valve  20 . The cooling channels  14  are connected to cooling channels (not shown) in the engine  10 . The radiator  16  emits heat to the environment. The coolant pump  18  pumps the coolant in the cooling circuit  12 . The thermostat valve  20  opens and closes the flow of the coolant through the radiator  16 , allowing the coolant to bypass radiator  16  into a parallel channel if the coolant temperature is below a predetermined threshold (approximately 90° C. in many typical engines).  
         [0016]    Referring additionally to FIG. 2, radiator  16  further comprises a main section  30 , from which the heat in the coolant is expelled to the environment. Main section  30  typically comprises parallel flattened metal tubes through which the coolant flows, mechanically coupled with metal fins to enhance the amount of heat which is expelled from the coolant to the environment. Representative portions of such tubes and fins are depicted with reference number  31  in FIG. 2. Radiator  16  also includes inlet tank  32  and outlet tank  34 , each of which is affixed to an end of main section  30 . Inlet tank  32  and outlet tank  34  are each preferably molded of plastic. Inlet tank  32  includes coolant inlet  36 , into which coolant flows from cooling circuit  12 , and outlet tank  34  includes coolant outlet  38 , out of which coolant flows back into cooling circuit  12  after having flowed through main section  30  to expel heat.  
         [0017]    The coolant channels in main section  30  of radiator  16  are at least partially coated with a catalytic material, a practice which is well-known in the art. The catalytic material is designed to convert an environmentally-harmful substance into one or more substances which are non-harmful to the environment, aided in this function by the heat of the coolant flowing in main section  30  of radiator  16 . Examples of environmentally harmful substances which may be so converted include particles, ozone, carbon monoxide, nitrous oxide, VOC, HC, NMOG, NO x , SO 2  and methane. Radiator  16  thus has a function to improve air quality. (The term “improve air quality” applies also in this application to components which have a role in reducing exhaust emissions from the vehicle.)  
         [0018]    Coupled to radiator  30 , preferably by molding into plastic inlet tank  32  near inlet  36 , is an identification device  39  which will be described further below. Identification device  39  is coupled by a communication channel, preferably a serial data bus  40 , to an electronic control unit (ECU)  42 . Rather than a data bus, appropriate numbers of conductors or wires can be used as well.  
         [0019]    In this embodiment of the present invention, ECU  42  is included in the engine control system for engine  10  and performs the numerous engine control functions performed by engine controllers. ECU  42  is therefore coupled to numerous sensors and actuators associated with engine  10  via bus(es) and/or conductor(s)  44 . As discussed above, ECU  42  is also communicatively coupled to identification device  39  and performs a diagnostic function related to determining whether a catalytically-coated radiator  16  is installed in the vehicle. (Due to the ready availability of data networks in modern vehicles, the diagnostic function can also be performed by another module than the engine controller or distributed among a number of controllers which together form a virtual diagnostic “device”, with data readily shared via data networks on the vehicle.)  
         [0020]    Refer now additionally to FIG. 3. Identification device  39  preferably includes two functional sections which are permanently coupled within identification device  39 . The first section  46  is an identifier which identifies radiator  16  as a radiator which is catalytically coated, as opposed to one which is interchangeable in the vehicle, but which is not catalytically coated. Second section  48  is a sensor which senses whether identification device  39  is actually installed in its appointed location (that is in this case, near inlet  36  to inlet tank  32 ). Preferably, this sensor is a sensor which senses the physical environment in the immediate vicinity of identification device  39 . More preferably, second section  48  is a temperature sensor and yet more preferably a temperature sensor of the simple thermistor type, well-known in the art to be very reliable.  
         [0021]    The functions of first section  46  and second section  48  of identification device  39  can, of course, be realized in several ways. In this embodiment of the present invention, first section  46  and second section  48  are realized within an integrated circuit which includes low-speed serial data capability with bus  40 . Preferably, this integrated circuit is a so-called local-interface network (LIN) chip, which is an integrated circuit having low-speed serial data communication capability and relatively low cost.  
         [0022]    In practice, ECU  42  periodically interrogates identification device  39  via bus  40  to ask whether radiator  16  is a catalytically-coated radiator. Identification device  39  (via first portion  46 ) will in turn answer this question by responding with the unique identification code assigned to catalytically-coated radiators. If identification device  39  does not reply to the interrogation with the appropriate answer, ECU  42  will conclude that the radiator in the vehicle is not a catalytically-coated radiator. ECU  42  will then take appropriate action, such as setting a malfunction code in its internal memory and/or lighting a malfunction indicator lamp  52 .  
         [0023]    However, ECU  42  receiving a correct answer to its interrogation does not necessarily assure the radiator is a catalytically-coated radiator. Because non-coated radiators are significantly less costly than coated radiators, and because non-coated radiators will be available as replacement parts intended for jurisdictions where radiators are not required and/or do not receive emission “credits”, there will be a significant incentive for creative measures to “trick” ECU  42  into thinking that an uncoated radiator which has been installed as a repair part is in fact a catalytically-coated one. One such creative measure could be to acquire an identification device  39  which has not been mounted into a radiator  16 , or one which has been removed from a catalytically-coated radiator  16 , and simply plug it into the connector intended for connection of identification device  39 . In such case, without additional countermeasures, ECU  42  would interrogate the identification device  39 , which would in turn respond that a coated radiator is installed in the vehicle (when in fact a non-coated radiator has been installed).  
         [0024]    Second section  48  of identification device  39  prevents this level of “cheating”. Second section  48 , preferably being a temperature sensor, senses the temperature in the immediate vicinity of identification device  39 . It has been observed by the inventors that at the inlet to radiator  16 , the temperature exhibits a very characteristic signature when thermostat  20  opens and allows coolant to flow into radiator  16 . This signature is illustrated in FIG. 4. As illustrated there, the temperature at the inlet to the radiator  16  makes a very substantial jump from a temperature approximately that of the engine compartment of the vehicle (approximately 40° C. in FIG. 4) to approximately 90° C. (the temperature at which thermostat  20  is designed to open) in a short time, approximately four seconds in the test plot shown in FIG. 4. ECU  42  can interrogate identification device  39  on a periodic basis and watch for this characteristic jump in temperature. If the characteristic jump is not seen during a number of warming-up events of the vehicle, ECU  42  will conclude that a catalytically-coated radiator  16  is not in fact installed in the vehicle. ECU  42  will then take appropriate measures to indicate this fault, including setting a malfunction code in its internal memory and/or lighting malfunction indicator lamp  52 .  
         [0025]    It can also be seen from FIG. 4 that the temperature near inlet  36  to radiator  16  will closely correspond to the engine coolant temperature after the characteristic jump mentioned in the foregoing paragraph occurs, and thereafter until coolant ceases to flow in radiator  16 . This relationship (that is, the close correspondence of temperatures between the engine coolant and the inlet to the radiator after coolant begins to flow in the radiator) can also be used as a way to sense whether identification device  39  is actually properly-installed in the radiator  16 . The engine coolant temperature is readily available in that it is already sensed outside radiator  16 , typically within engine  10 , for various engine control purposes. A coolant temperature sensor  53  is shown schematically in FIG. 1.  
         [0026]    Because first section  46  and second section  48  are realized on a common integrated circuit which is mounted on a substrate or circuit board, they can be said to be “permanently” coupled together and “permanently” coupled within identification device  39 . “Permanent” coupling in this context means that such coupling cannot practically be undone and the respective components still function properly. It is desirable for first section  46  and second section  48  to each be permanently coupled within identification device  39  to minimize chances of “cheating”. Such “permanent” coupling can also be attained, for example, by first section  46  and second section  48  being located on a common substrate, though not necessarily integrated into the same integrated circuit.  
         [0027]    The invention is not limited to the above-described embodiments, but may be varied within the scope of the following claims.