JP3754212B2 - Warning light failure diagnosis device and method for internal combustion engine, and control method at failure - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a warning light failure diagnosis device, method, and control method for a failure of an internal combustion engine, and more particularly, diagnoses a failure of a warning light that lights when a failure occurs and informs the driver of the failure, and warns the driver when a failure occurs. The present invention relates to a warning lamp failure diagnosis device, method and control method for a failure of an internal combustion engine that secures an alternative warning means for the lamp.
[0002]
[Prior art]
The conventional engine control device is provided with means for performing failure determination when any of the control devices fails, and lighting a warning lamp at the time of failure to warn the driver of an abnormality.
[0003]
As an engine control device provided with such a warning light, for example, in Japanese Patent Laid-Open No. 9-125938, the deterioration of a catalyst for purifying engine exhaust gas is determined, and if the deterioration is determined, the warning light is turned on. Proposing technology.
[0004]
[Problems to be solved by the invention]
The conventional method realizes that the driver is informed of an abnormality by turning on a warning lamp when it is determined that the engine device has failed.
[0005]
However, when the warning light and warning light control line that should report an abnormality breaks down, the method of transmitting the abnormality to the driver is impaired, and the driver cannot recognize the abnormality of the engine. There is.
[0006]
The object of the present invention was made in view of such a problem, and reliably diagnoses the failure of the warning light and the warning light control line. For example, a failure occurs in the warning light and the warning light control line itself. Even in such a case, an object of the present invention is to provide a warning lamp failure diagnosis device, method, and control method for failure of an internal combustion engine that can transmit an abnormality of a control system to a driver.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is characterized in that warning light failure diagnosis conditions are set based on detection signals taken from various sensors of the internal combustion engine control system and failure signals output from the failure determination means. Determining and detecting a failure of the warning light and the warning light control line based on the determined warning light failure diagnosis condition, and confirming based on the confirmation by comparing the detected failure with a predetermined confirmation condition It is to control the internal combustion engine.
[0008]
Specifically, the present invention provides the following apparatuses and methods.
[0009]
The present invention includes an input processing means for capturing detection signals from various sensors of an internal combustion engine control system, a failure determination means for determining whether or not a failure has occurred based on the captured detection signals, and outputting a failure signal, and the output An internal combustion engine comprising: a warning light lighting means for outputting a lighting signal based on the failure signal thus generated to light a warning light; and a warning light failure diagnosis means for diagnosing a failure of the warning light and the warning light control line. Provide a warning light failure diagnosis device.
[0010]
Preferably, the warning lamp failure diagnosis means determines a warning lamp failure diagnosis condition based on a detection signal input from the input processing means and a lighting signal output from the warning lamp lighting means. Detection necessity determination means, warning light failure detection means for detecting a failure of the warning light and warning light control line based on the determined warning light failure diagnosis condition, and the detected failure are preset. And a warning light failure determination means for determining and confirming by comparing with the confirmation condition.
[0011]
Preferably, the warning lamp failure diagnosis means determines a warning lamp failure diagnosis condition based on a detection signal input from the input processing means and a lighting signal output from the warning lamp lighting means. Detection necessity determination means, warning light failure detection means for detecting a failure of the warning light and warning light control line based on the determined warning light failure diagnosis condition, and the detected failure are preset. And a warning light failure determination means for making a final determination in comparison with a final condition, and a fail-safe control means for performing a fuel-cut fail-safe control based on the determined failure result and the output failure signal. Have.
[0012]
Preferably, the warning light failure determination means determines that a failure has occurred when the detected failure state of the warning light and the warning light control line continues for a predetermined time or a predetermined number of times.
[0013]
Preferably, when the fail safe control means determines that the internal combustion engine control system has failed based on the determined failure result and the output failure signal, the rotational speed of the internal combustion engine is predetermined. The fuel is cut to the fuel injection valve so as not to rise above the value.
[0014]
Further, the present invention determines whether or not a failure has occurred based on detection signals acquired from various sensors of the internal combustion engine control system, outputs a lighting signal based on the failure signal output based on the determination result, and Based on the detection signal and the output lighting signal, to determine the warning light failure diagnostic condition, based on the determined warning light failure diagnostic condition, to detect a failure of the warning light and warning light control line, There is provided a warning lamp failure diagnosis method for an internal combustion engine, wherein the detected failure is determined by comparing with a predetermined determination condition.
[0015]
Further, the present invention determines whether or not a failure has occurred based on detection signals acquired from various sensors of the internal combustion engine control system, outputs a lighting signal based on the failure signal output based on the determination result, and Based on the detection signal and the output lighting signal, to determine the warning light failure diagnostic condition, based on the determined warning light failure diagnostic condition, to detect a failure of the warning light and warning light control line, The detected failure is determined by comparing with a predetermined determination condition, and fuel-cut fail-safe control is performed based on the determined failure result and the output failure signal. Provided is a control method for a warning light failure of an internal combustion engine.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a warning lamp failure diagnosis device, method, and failure control method for an internal combustion engine according to an embodiment of the present invention will be described with reference to the drawings.
[0017]
FIG. 1 shows an overall configuration of an engine system provided with a failure control apparatus according to an embodiment of the present invention. As shown in FIG. 1, the air to be taken in by the engine 8 is taken from the inlet portion 2 of the air cleaner 1, passes through a throttle valve device 6 provided with a throttle valve 5 for controlling the amount of intake air, and enters the collector 7.
[0018]
The throttle valve 5 is connected to the motor 10, and the throttle valve 5 is operated by driving the motor 10. The throttle valve 5 is operated to control the intake air amount. The intake air reaching the collector 7 is distributed to the intake air pipes 9 connected to the cylinders 23 of the engine 8 and guided into the cylinders 23.
[0019]
On the other hand, fuel such as gasoline is sucked and pressurized from a fuel tank 11 by a fuel pump 12 and then supplied to a fuel system 24 in which a fuel injection valve (injector) 13 and a variable fuel pressure pressure regulator 14 are piped.
[0020]
The fuel system is regulated to a predetermined pressure by the variable fuel pressure regulator 14 described above, and is injected into the cylinders 23 from the injectors 13 that open the fuel injection ports of the respective cylinders 23. Further, a signal representing the intake flow rate is output from the air flow meter 3 and is input to the control unit 15.
[0021]
Further, a throttle sensor 18 for detecting the opening degree of the throttle valve 5 is attached to the throttle valve device 6, and its output is also input to the control unit 15.
[0022]
Next, 16 is a crank angle sensor, which is rotationally driven by the camshaft 25 and outputs a signal representing the rotational position of the crankshaft. This signal is also input to the control unit 15.
[0023]
Reference numeral 20 denotes an A / F (air / fuel ratio) sensor provided in the exhaust pipe 26, which detects and outputs the actual operating air / fuel ratio from the components of the exhaust gas so that the signal is also input to the control unit 15. It has become.
[0024]
This control unit 15 has a processing means (CPU) 27 and takes in various signals for detecting the operating state of the engine such as the aforementioned crank angle signal and throttle opening signal as input signals, and executes predetermined calculations. Then, various control signals calculated as the calculation results are output, and predetermined signals are output to the injector 13, the ignition coil 17, and the motor 10 for operating the throttle valve, and the fuel supply control, the ignition timing control, the intake air Perform volume control.
[0025]
Reference numeral 28 denotes a warning light that is turned on to notify the driver of an abnormality when any of these various control systems fails.
[0026]
FIG. 2 shows a control system in the control unit 15 of FIG. Note that, in the drawings described below, the same reference numerals are given to portions common to FIG.
[0027]
The control unit 15 includes a CPU 15a that is the center of control, an input processing circuit 15b that performs predetermined processing (for example, A / D conversion) on detection signals from various sensors, which will be described later, and a bus that transfers data. 15c and an output processing circuit 15d that outputs data that has been subjected to predetermined arithmetic processing by the CPU 15a.
[0028]
The input processing circuit 15b receives detection signals from the crank angle sensor 17, the throttle sensor 18, the accelerator sensor 107, the water temperature sensor 108, the air flow meter 3, the ignition switch 109, the starter switch 110, and the battery voltage 111, and these signals. Is subjected to predetermined processing by the input processing circuit 15b, converted into data, and then supplied to the CPU 15a via the bus 15c.
[0029]
Further, an interrupt signal is given to the interrupt controller 104 from the input processing circuit 15b.
[0030]
When various types of detection data are given via the bus 15c, the CPU 15a performs arithmetic processing on the various types of detection data based on a predetermined program stored in the ROM 101, and then stores the calculated data in the RAM 102, While being stored in the backup RAM 106, a control signal is output to the warning lamp 28, the injectors 13a to 13d, the throttle motor 10, the fuel pump 12, and the igniter 17 via the output processing means 15d.
[0031]
FIG. 3 shows a functional configuration of the failure control apparatus according to the embodiment of the present invention.
As shown in FIG. 3, the failure control device includes an input processing unit 301, a failure determination unit 302, a warning lamp lighting unit 303, and a warning lamp failure diagnosis unit 304.
[0032]
The input processing means 301 takes in detection signals from the battery voltage 111, the crank angle sensor 17, the air flow meter 3, the accelerator sensor 107, and the like when a failure occurs in the control system of the internal combustion engine.
[0033]
The failure determination means 302 determines whether or not a failure has occurred based on the output signals of the various sensors that have been taken in, and outputs a failure signal.
[0034]
The warning lamp lighting means 303 outputs a lighting signal based on the output failure signal and lights the warning lamp 28.
[0035]
The warning light failure diagnosis means 304 diagnoses a failure of the warning light 28 and the warning light control line.
[0036]
The warning light failure diagnosis means 304 includes warning light failure detection necessity determination means 3041, warning light failure detection means 3042, warning light failure determination means 3043, and fail-safe control means 3044.
[0037]
The warning lamp failure detection necessity determination unit 3041 is based on the detection signal input from the input processing unit 301 and the lighting signal output from the warning lamp lighting unit 303, for example, a condition that allows warning lamp failure diagnosis to be performed reliably. It is determined whether the voltage of the battery voltage 111 for operating the system is sufficient.
[0038]
The warning light failure detection means 3042 detects whether or not the warning light 28 and the warning light control line are out of order when the warning light failure diagnosis condition is established (permitted).
[0039]
The warning light failure determination unit 3043 determines whether or not the result detected by the warning light failure detection unit 3042 is a false detection, and determines the failure. That is, when the detected failure state of the warning light and the warning light control line continues for a predetermined time or a predetermined number of times, it is determined to be a failure.
[0040]
The fail safe control means 3044 performs fail safe control to the injectors 13a to 13d based on the confirmed result from the warning light failure determination means 3043 and the failure signal output from the failure determination means 302.
[0041]
If the engine control system components, such as sensors and actuators, do not fail only due to a warning light failure, there is no problem in running even if fail-safe is not executed.
[0042]
FIG. 4 shows the lighting control of the warning lamp 28 of FIG. 1, and the warning lamp 28 is provided on the inter-panel 30 of the driver's seat as shown in FIG. The warning lamp 28 is turned on by power from the battery voltage VB. Further, for example, the transistor Tr is driven by the CPU 15a in the control unit 15, and the warning lamp 28 is turned on when the Tr is driven.
[0043]
Further, in order to detect disconnection and short circuit between the warning lamp 28 and the transistor Tr, a voltage generating resistor R and a warning lamp voltage detection circuit 15e are provided between the warning lamp 28 and the transistor Tr.
[0044]
On the other hand, for example, when a disconnection occurs in the portion A of the control line in FIG. 4, as shown in the warning lamp failure diagnosis input / output table in FIG. 5, the warning lamp lighting output (the base output from the CPU 15a to the transistor Tr) is When Low, no voltage is generated in the voltage generation circuit R even when the transistor Tr is in an off state, so that the warning lamp lighting input IC read value (signal from the warning lamp voltage detection circuit 15e to the CPU 15a) becomes Low.
[0045]
In addition, when a short circuit occurs in the portion A of the control line in FIG. 3, as shown in FIG. 5, when the warning lamp lighting output (the base output from the CPU 15a to the transistor Tr) is High, the transistor Tr is in the on state. However, since the voltage is generated in the voltage generation circuit R, the warning lamp lighting input IC read value (signal from the warning lamp voltage detection circuit 15e to the CPU 15a) becomes High. Based on the above, it is determined that the warning lamp 28 is disconnected and has a short circuit failure.
[0046]
FIG. 6 shows a flowchart for diagnosing disconnection and short-circuit failure of the warning lamp 28. As described with reference to FIG. 4, the disconnection and short failure determination is performed based on the relationship between the output of the CPU 15 a and the output of the voltage detection circuit 15 e.
[0047]
That is, in step 601, permission to detect a warning lamp failure is determined. For example, if the battery voltage 111 is too low, the detection permission determination condition here is determined according to the voltage state of the battery voltage 111 or the like because the control system malfunctions and accurate failure diagnosis cannot be performed.
[0048]
Next, in step 602, a warning lamp lighting control state is detected according to failure determination of various sensors such as the crank angle sensor 17, the air flow meter 3, and the accelerator sensor 107 shown in FIG.
[0049]
Next, when the warning lamp lighting control is performed, the output value of the warning lamp voltage detection circuit 15e is fetched at step 603. As described in FIG. 5, when the warning lamp lighting control is performed, that is, when a high signal is output from the CPU 15a to the transistor Tr, the warning lamp voltage detection circuit 15e outputs a low output to the CPU 15a. Thus, the CPU 15a determines that there is no short circuit.
[0050]
On the other hand, for example, when a short circuit occurs in the portion A of FIG. 4, as described above, the warning lamp voltage detection circuit 15e becomes High to the CPU 15a when the High signal is output from the CPU 15a to the transistor Tr. Thus, the CPU 15a determines that there is a short circuit.
[0051]
If it is determined that there is a short circuit, the MILSCNT counter counts up in step 604, and in step 605, it is determined whether or not the counter value has reached a specified NG (MILSNG) value. Here, the reason why the prescribed NG value is provided is to prevent a misdiagnosis caused by counting up the MILSCNT counter due to noise or the like by setting the prescribed NG value as a predetermined value.
[0052]
On the other hand, when it is determined in step 603 that there is no short-circuit, in step 606, the MILSCNT counter is cleared.
[0053]
Next, when the warning lamp lighting control is not performed in step 602, the output value of the warning lamp voltage detection circuit 15e is fetched in step 607 as in step 603. As described with reference to FIG. 5, when the warning lamp lighting control is not performed, that is, when a Low signal is output from the CPU 15a to the transistor Tr, the voltage detection circuit 15e outputs a High output to the CPU 15a. The CPU 15a determines that there is no disconnection.
[0054]
On the other hand, for example, when a disconnection occurs in the portion A in FIG. 4, as described above, when the Low signal is output from the CPU 15a to the transistor Tr, the warning lamp voltage detection circuit 15e becomes Low to the CPU 15a. Thus, the CPU 15a determines that there is a disconnection.
[0055]
If it is determined that there is a disconnection, in step 608, the MILDCNT counter counts up, and in step 609, it is determined whether or not the counter value has reached a prescribed NG (MILLDNG) value. Here, the reason why the prescribed NG value is provided is that the prescribed NG value is set to a predetermined value to prevent erroneous diagnosis due to the count-up of the MILDCNT counter caused by noise or the like.
[0056]
On the other hand, when it is determined in step 607 that there is no disconnection, in step 610, the MILDCNT counter is cleared.
[0057]
Next, in step 611, when it is determined in step 605 or step 609 that the warning light 28 is disconnected or a short-circuit failure, it is determined that the warning light 28 and the warning light control line are defective.
[0058]
FIG. 7 shows a flowchart after it is determined that the above-mentioned warning lamp failure has occurred. In step 701, for example, if an NG determination is made in either step 605 (warning lamp disconnection failure detection) or step 609 (warning light short failure detection) shown in FIG. 6, there is a warning light lighting request in step 702. To determine.
[0059]
At this time, since the warning lamp 28 and the warning lamp control line are out of order, lighting according to the warning lamp lighting control request cannot be performed. Accordingly, when there is a warning lamp lighting request, that is, when there is a warning lamp lighting request due to a malfunction of the control system of the internal combustion engine, it is determined in step 703 whether the engine speed is equal to or greater than a predetermined value (MILNGFC). If it is equal to or greater than the predetermined value, fuel cut is performed in step 704. When the fuel is cut, the engine speed decreases, so that the driver can detect an engine abnormality even in a failure state in which the warning light cannot be turned on.
[0060]
Even when the warning light failure is determined in step 701, when there is no warning light lighting request in step 702, that is, when the warning light 28 and the warning light control line are simply broken, the above-described operation such as fuel cut is performed. Nothing is done because there is no need to give an alternative warning to the person.
[0061]
Next, when it is determined in step 705 that the engine speed has fallen below a predetermined value (MILNGRC) due to the fuel cut in step 704, fuel cut recovery (resumption of fuel injection) is performed in step 706. This prevents engine stall (engine stall) due to fuel cut control in step 704.
[0062]
【The invention's effect】
According to the present invention, the failure diagnosis of the warning light and the warning light control line is reliably performed, and even if a failure occurs in the warning light and the warning light control line itself, the abnormality of the control system is notified to the driver. Since it can be communicated, higher safety can be ensured.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an engine system provided with a failure control apparatus according to an embodiment of the present invention.
FIG. 2 is a configuration diagram of a control system in the control unit of FIG. 1;
FIG. 3 is a functional configuration block diagram of a failure control apparatus according to an embodiment of the present invention.
4 is a diagram illustrating lighting control of a warning lamp 28 in FIG. 1. FIG.
FIG. 5 is an input / output characteristic diagram of warning lamp diagnosis applied to the present invention.
FIG. 6 is a flowchart for diagnosing disconnection and short-circuit failure of a warning light and a warning light control line.
7 is a flowchart after the warning light failure is determined in FIG. 6. FIG.
FIG. 8 is a layout diagram of warning lights applied to FIG. 1;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 301 ... Input processing means 302 ... Failure determination means 303 ... Warning light lighting means 304 ... Warning light failure diagnosis means 3041 ... Warning light failure detection necessity determination means 3042 ... Warning light failure detection means 3043 ... Warning light Failure determination means, 3044... Fail-safe control means

Claims (3)

Input processing means for capturing detection signals from various sensors of the internal combustion engine control system, failure determination means for determining whether or not a failure has occurred based on the detected detection signals, and outputting a failure signal, and the output failure signal A warning light failure diagnosis device for an internal combustion engine having warning light lighting means for outputting a lighting signal based on the warning light and lighting warning light for diagnosing a failure of the warning light and the warning light control line.
The warning light failure diagnosis means is a warning light failure detection necessity determination means for determining the warning light failure diagnosis condition based on the detection signal input from the input processing means and the lighting signal output from the warning light lighting means. And warning light failure detection means for detecting a failure of the warning light and the warning light control line based on the determined warning light failure diagnosis condition, and comparing the detected failure with a predetermined determination condition. The warning light and the warning light control line thus detected have a warning light failure determination means for determining a failure when the failure state continues for a predetermined time or a predetermined number of times, and the determined failure result and the output are output. An alarm lamp failure diagnosis device for an internal combustion engine, comprising failsafe control means for performing failsafe control of fuel cut based on the failure signal.   2. The warning light failure diagnosis apparatus for an internal combustion engine according to claim 1, wherein the fail safe control means performs a fuel cut to a fuel injection valve so that the rotational speed of the internal combustion engine does not increase to a predetermined value or more. . The presence / absence of a failure is determined based on detection signals captured from various sensors of the internal combustion engine control system, a lighting signal is output based on the failure signal output based on the determination result, and the captured detection signal and the output are output. The warning light failure diagnosis condition is determined based on the lighting signal, and the warning light and warning light control line failure is detected based on the determined warning light failure diagnosis condition, and the detected failure is detected. In the warning lamp failure diagnosis method for an internal combustion engine that is determined by comparing with a predetermined determination condition,
When the failure state of the detected warning light and warning light control line continues for a predetermined time or a predetermined number of times, it is determined to be a failure,
An internal combustion engine warning light failure control method, comprising: performing a fuel-cut fail-safe control based on a determined failure result and the output failure signal.

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