JP3417754B2 - Vehicle diagnostic device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle diagnostic device, and more particularly to a vehicle diagnostic device that communicates with an on-vehicle electronic control device mounted on a vehicle and performs vehicle diagnostics based on the communication result. More specifically, the present invention relates to a vehicle diagnostic device capable of diagnosing an engine speed in a short time even when a diagnostic method in which a plurality of diagnoses are cyclically repeated in a very short cycle is adopted.

[0002]

2. Description of the Related Art In recent years, in order to improve an engine control function, engine ignition timing control, valve opening / closing timing control, or electronic fuel injection system (EFI) in an automobile (hereinafter referred to as "vehicle") is used. Fuel injection control and the like have come to be performed by an in-vehicle electronic control unit (ECU) equipped with a microcomputer. The ECU includes various sensors such as a temperature sensor for detecting the temperature of the engine cooling water, a rotation sensor for detecting the engine speed, a vehicle speed sensor for detecting the vehicle speed, an O2 sensor for detecting the oxygen concentration in the exhaust gas, and a brake pedal. Various switches such as a brake switch for detecting that the pedal is depressed are connected, and the ECU performs various controls based on detection signals output from various sensors.

In a production process for manufacturing a vehicle equipped with such an ECU, it is necessary to diagnose whether or not each sensor or the ECU itself is functioning normally in a final inspection process after the vehicle is assembled. Fairness 3-593
In Japanese Patent Laid-Open No. 72, a diagnosis method is proposed in which a vehicle-diagnosis program is executed by a diagnosis device equipped with a microcomputer, and a diagnosis regarding a desired diagnosis item is performed at a scheduled timing.

Further, in a failure diagnosis targeting a plurality of diagnostic items, the plurality of diagnostic items are diagnosed in a predetermined order as described in Japanese Patent Publication No. 61-25091, for example. The result of the pass / fail judgment was sequentially output on the display device.

[0005]

The vehicle diagnostic item includes, for example, "Ne diagnosis" for determining whether or not the engine speed Ne during idling falls within a predetermined range. The condition is not necessary at all, and the diagnosis is completed in an instant, such as the diagnosis that requires preconditions such as that it is sufficiently warmed and the "brake switch diagnosis" that diagnoses the opening / closing function of the brake switch. There is a possible diagnosis.

In addition, when a plurality of these diagnostic items are prepared, the diagnostic order of each diagnostic item is determined in advance in the conventional vehicle diagnostics, etc., until the previous diagnostic is completed and its quality is judged. The next diagnosis cannot be made. Therefore, if it is specified that "Brake switch diagnosis" should be performed after "Ne diagnosis", the operator can perform "Brake switch diagnosis" until the engine is sufficiently warmed up and "Ne diagnosis" is completed. However, there is a problem that a wasteful waiting time is generated during the work, and as a result, the operator's restraining time, that is, the working time becomes long.

Moreover, if the diagnosis sequence is previously determined as described above, the sequence and timing of various operations (in the case of "brake switch diagnosis", the operation of depressing the brake pedal) that the operator should perform for each diagnosis item. There is also a problem that work efficiency decreases because there are many restrictions regarding.

As one of the diagnostic methods for solving such a problem, each diagnostic is cyclically repeated at a very short cycle regardless of whether it is successful or not, and a diagnostic item which has not passed even after the lapse of the scheduled time is regarded as a failure. A diagnostic method for diagnosing can be considered. When such a diagnosis method is adopted, for example, if the diagnosis cycle is set so that one cycle of the diagnosis is completed while the operator is pressing the brake pedal, no matter what order and timing the brake pedal is pressed, ,
Since the "brake switch diagnosis" is always executed during that period, restrictions on the sequence and timing of various operations to be performed for each diagnosis item are reduced, and work efficiency is dramatically improved.

However, for example, in the "Ne diagnosis", it is necessary to actually measure the engine speed Ne and compare the measured value with a reference value to judge whether the engine speed Ne is good or bad. It takes a relatively long time. Therefore, if "Ne diagnosis" is incorporated as one of the diagnostic items of the diagnostic method in which the diagnostic items are cyclically repeated as described above, the diagnostic cycle becomes longer, so the diagnostic item is performed for each diagnostic item. This may cause a problem of increasing restrictions on the order and timing of various operations that should be performed.

The object of the present invention is to solve the above-mentioned problems of the prior art and to make a diagnosis even if "Ne diagnosis" is incorporated as one of the diagnosis items of a diagnostic method in which the diagnosis of a plurality of diagnostic items is cyclically repeated. An object of the present invention is to provide a vehicle diagnostic device capable of reducing restrictions on the order and timing of various operations to be performed for each item.

[0011]

In order to achieve the above-mentioned object, in the present invention, a vehicle diagnosis for diagnosing a plurality of types of items based on various data obtained from an on-vehicle electronic control unit via a communication means. The device is characterized in that the following measures are taken. (1) Circulation diagnostic means for cyclically executing a plurality of types of diagnostics to judge pass / fail of each diagnostic, engine rotational speed detection means for detecting the engine rotational speed at each diagnostic timing, and And an engine revolution number accumulating unit that accumulates the engine revolution number, an accumulated number storage unit that stores the accumulated number of engine revolutions, and an average value of the engine revolutions based on the accumulated value and the accumulated number of engine revolutions. The average value calculating means, the comparing means for comparing the average value with a predetermined reference value, and the diagnosis executing means for performing the engine speed diagnosis based on the comparison result are provided. (2) Cyclical diagnostic means for cyclically executing a plurality of types of diagnostics to judge pass / fail for each diagnostic, and engine speed detecting means for detecting the engine speed at each diagnostic timing. And an engine speed accumulating means for accumulating the engine speed, and a target speed detecting means for detecting a target engine speed determined by the on-vehicle electronic control device according to the engine load each time the engine speed is detected. A target engine speed accumulating means for accumulating the target engine speed, an accumulative number storage means for storing the accumulative number of engine revolutions, an average value of the engine revolutions based on the integrated value of the engine revolutions and the accumulative number. And a second average value calculating means for calculating an average value of the target engine speed based on the integrated value of the target engine speed and the number of times of integration. A mean value calculating means, a comparing means for comparing each average value, and a diagnosis executing means for making an engine speed diagnosis based on the comparison result are provided.

According to the above configuration (1), the detected value of the engine speed is integrated every time the engine speed diagnosis is repeatedly executed, and the average value of the engine speed is calculated based on the integrated value. Therefore, one "Ne diagnosis" can be performed in a short time.

According to the above-mentioned structure (2), the engine speed can be diagnosed even when the engine load is generated.

[0014]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail below with reference to the drawings. Figure 1 shows the ECU installed in the vehicle to be diagnosed.
1 is a block diagram showing a configuration of an embodiment of a vehicle diagnostic device 2 that is used by being connected to the ECU 1 and the ECU 1. FIG.
2 to 5 show R inserted in the vehicle diagnostic device 2 shown in FIG.
FIG. 7 is a diagram schematically showing the stored contents of the OM card 7, and FIG. 6 is a diagram showing a display example of the diagnosis result displayed on the display unit 27. FIG. 7 is a functional block diagram of a vehicle diagnostic device to which the present invention is applied. FIG. 8 is a flow chart showing an outline of the vehicle diagnosis according to the present invention, and FIGS. 9 to 16 are flow charts specifically showing the operation of each diagnosis process constituting the vehicle diagnosis.

In FIG. 1, the ECU 1 includes a CPU 10,
It is composed of a ROM 11, a RAM 12, a driver 13, an A / D converter 14, and a communication interface 15. The ECU 1 is connected to peripheral devices via connectors 16 and 17, for example, various actuators 3 are connected to the connector 16, and various sensors 4 and switches 4 are connected to the connector 17. In addition, the communication cable 5 of the vehicle diagnostic device 2 is connected to the connector 18 as
4 are connected.

A signal input from each sensor 4 etc. to the ECU 1 is converted into a digital signal by the A / D converter 14 and then converted into a CP signal.
Captured by U10. The signal captured by the CPU 10 is
It is processed according to the control data stored in the ROM 11 and the RAM 12, and the control program written in the ROM 11. CPU 10 for driver 13
The instruction signal corresponding to the processing result of
Supplies power to the actuator 3 in response to this instruction signal. In addition to the programs, the ROM 11 stores each E
An identification code unique to CU1, that is, an ECU code is also registered.

On the other hand, the vehicle diagnostic device 2 according to the present invention has a CPU
20, ROM 21, RAM 22, transmission unit 24, communication interface 25, and power supply unit 29. The power supply unit 29 serves as a power supply for the vehicle diagnostic device 2.
In-vehicle battery 19 and built-in battery 2 of the vehicle to be diagnosed
Either one of the three is selected. In addition, the vehicle diagnostic device 2 includes a keyboard 26 for inputting an instruction by an operator and a display unit 27 for displaying a processing result by the CPU 20.
In addition, a bar code reader 31 and a bar code interface 32 for reading the bar code displayed identification code are provided. In the present embodiment, as the display unit 27, a liquid crystal display panel with a backlight (LC
D) is adopted. The keyboard 26 is provided with general numeric keys, cursor movement keys, function keys and the like.

The communication cable 5 has a signal line 51 and a power supply line 52, and the communication interface 15 of the ECU 1 and the communication interface 25 of the vehicle diagnostic device 2 are connected via the signal line 51 of the communication cable 5, and CP
It is configured to enable bidirectional digital communication between the U10 and the CPU 20. When the communication cable 5 is connected to the ECU 1, the power supply unit 29 uses the electric power supplied from the in-vehicle battery 19 via the power supply line 52 as the electric power source of the vehicle diagnostic device 2, and the electric power causes the built-in battery 23 to operate. To charge.

As will be described later in detail, the vehicle diagnostic device 2 is started without turning on a key switch for turning on the power provided on the keyboard 26 or by operating the key switch at all. The operator uses the communication cable 5
Is performed by connecting the connector 34 to the connector 18 of the ECU 1, and the operation after the activation differs depending on which method the activation is performed.

The ROM 21 stores a basic program and control data necessary for controlling the vehicle diagnostic device 2, and the non-standard data used in each diagnosis and the vehicle diagnostic program are accompanied by production of a new model vehicle. Unique information that can be added or changed is stored in the ROM card 7. The data of the ROM card 7 is taken into the CPU 20 via the ROM card interface 28.

The signal fetched from the ECU 1 is stored in the ROM 2
1 and the basic data stored in the RAM 22, and the vehicle diagnostic program and control data stored in the ROM card 7, the processing result, that is, the diagnostic result is temporarily stored in the RAM 22. This diagnosis result is output to the display unit 27 every time the diagnosis of each vehicle is completed, and the diagnosis results of several vehicles are transmitted from the transmission unit 24 to a host device such as the host computer 30 in response to an instruction from the operator. The data is collectively transmitted, and is centrally managed and stored by the host computer 30 and the large-sized storage device 33. Further, the vehicle diagnostic device 2 can be connected to a personal computer (not shown), and the personal computer can provide the vehicle diagnostic device 2 with necessary information, for example, an updated (upgraded) failure diagnostic program.

As shown in FIG. 2, the ROM card 7 is a vehicle in which a diagnostic item management table 71 for selecting a diagnostic item based on an ECU code and a vehicle diagnostic program for a plurality of diagnostic items are stored. A diagnostic program storage area 72, a standard data storage area 73 storing standard data shared by each vehicle regardless of the ECU,
A non-standard data storage area 74 in which unique non-standard data different depending on each ECU is stored is secured.

FIG. 3 is a diagram showing an example of the stored contents of the diagnostic item management table 71. The vehicle diagnostic device 2 of the present invention is capable of diagnosing a large number of items and includes all algorithms for each diagnostic item. However, not all of the diagnostics are executed for all vehicles, and each vehicle is not individually diagnosed. The diagnostic items to be executed are different. Therefore, in the management table 71, "1" (selected) or "0" (non-selected) is registered for each ECU code for each diagnostic item. For example, "○ Δ × □" is registered as the ECU code. The diagnostic items that are selectively executed for the currently-executed vehicle are 1, 2, 5, 6, ... And the other diagnostic items are not executed.

FIG. 4 is a diagram showing an example of the storage contents of the non-standard data storage area 74. In this embodiment, EC
As the non-standard data different for each U (that is, ECU code), for example, a unique idling rotation speed NID-ref is registered in association with each ECU code.

The specific idling speed NID-ref is, as will be described in detail later, a reference speed during idling specified for each ECU code, and whether the engine speed during idling is normal or not. Diagnosis is performed by comparing the detected engine speed Ne with a unique idling speed NID-ref selected according to the ECU code of the vehicle.

As described above, in this embodiment, different diagnostic contents, that is, a combination of diagnostic items and non-standard data are automatically determined according to the ECU code, so that the operator selects the diagnostic item and the non-standard data. Free yourself from the work of determining data. Therefore, not only the burden on the operator is alleviated, but also an erroneous selection of a diagnostic item and an erroneous recognition of non-standard data are eliminated, so that an accurate diagnosis can be performed.

FIG. 5 is a diagram showing the stored contents of the standard data storage area 73, in which standard data x1 to x5 which are commonly used in each diagnosis are stored regardless of the ECU code in the diagnostic program.

Next, an operation example of this embodiment will be described in detail with reference to the flowchart. FIG. 8 is a flowchart showing an outline of vehicle diagnosis by the vehicle diagnosis apparatus of the present invention. The vehicle diagnostic device of the present invention can be used for vehicle diagnostics in any environment, such as vehicle diagnostics on a production line or vehicle diagnostics at a repair shop, but here, "inspection process" or the like on a factory production line. The operation will be described by taking as an example the case of use in the "vehicle diagnosis" carried out in 1.

In step S100, "initial processing" is executed. In step S200, the "vehicle speed sensor diagnosis" registered as the diagnosis item 1 is executed. In step S300, the “EG
R diagnosis ”is executed. In step S600, the "Ne diagnosis" registered as the diagnosis item 3 is executed.
This "Ne diagnosis" is a characteristic feature of the present invention, and will be described later in detail with reference to the functional block diagram of FIG. 7 and the flowcharts of FIGS. In step S700, the diagnosis of each switch system registered as the diagnosis items 4, 5, ... Is executed. In step S800, "end processing" is executed. In step S900, "standby mode processing" is executed. Then, the process is step S
Returning to 200, each diagnosis is repeated until all the diagnoses pass.

As described above, the vehicle diagnostic apparatus of the present invention is configured to repeatedly and automatically and repeatedly perform diagnostics on a large number of items. Hereinafter, each diagnostic method and processing method will be described in detail.

FIG. 9 is a flow chart showing the operation of "initial processing" executed as step S100. As described above, the vehicle diagnostic device 2 of the present embodiment is started up either by the operator operating the key switch for turning on the power provided on the keyboard 26 or by the operator connecting the communication cable 5 to the ECU 1. Any of the above is possible, and in the initial processing, it is first determined by which method the power was turned on.

In step S101, it is determined whether or not the power source of the vehicle diagnostic device 2 is turned on by turning on a switch, and if it is determined that it is turned on, step S10 is performed.
In 4, the flag Fst indicating the power-on procedure is set to "0". At this time, power supply to the vehicle diagnostic device 2 is performed by the built-in battery 23. In addition, the step S10
If it is not detected that the power is turned on by the switch ON operation in 1, it is determined in step S102 whether or not the communication cable 5 is connected to the vehicle (ECU 1), and if it is detected that the communication cable 5 is connected, step S103. At "1", the flag Fst is set. The power supply at this time is performed by the vehicle-mounted battery 19.

When it is detected that the power is turned on by turning on the switch or the cable is connected, an initial screen is displayed on the display unit 27 in step S105, and in step S106, an abnormality or failure of itself is checked. Self-diagnosis is performed in order to do so. Step S1
If the self-diagnosis result is determined to be good in 07, the process proceeds to step S108, and if it is determined to be bad, an error message is displayed on the display unit 27 in step S119.

In step S108, the flag Fst is checked in order to determine whether the operator should select a process to be executed on the menu screen or to automatically start a predetermined specific process. It
When the flag Fst = "1", that is, when the power is turned on by the cable connection, the "vehicle diagnosis" is immediately activated as a specific process determined in advance without displaying the menu screen on the display unit 27, The process proceeds to step S109. In step S109, the ECU code registered in the ECU 1 is read. In step S110, based on the read ECU code,
The diagnostic item management table 71 described with reference to FIG. 3 is searched, and the diagnostic item to be executed is selected. In step S111, the diagnosis selection flag F of the selected diagnosis item
selcxx ("xx" is the diagnostic item number) is "1" (selection)
Is set, and "0" (non-selected) is set in the diagnosis selection flag Fselcxx of the unselected diagnosis item.

In step S112, a list of diagnostic item numbers representing the selected diagnostic items is displayed on the display unit 27.
FIG. 6A is a diagram showing a display example of the display unit 27 when all diagnostic items are selected, and all diagnostic item numbers “01”, “02”, “03” ... Are displayed. ing. As will be described in detail later, the display "00" in the figure is a code that is erased when the diagnosis start condition regarding the "Ne diagnosis" of the diagnosis item 3 is satisfied and the diagnosis is sufficiently performed. Displayed in step S113. The code is not limited to "00", and may be an alphabet such as "X" or another symbol as long as it is a code that can be easily distinguished from other diagnostic item numbers.

In step S114, the identification code representing the identification information unique to each vehicle as a barcode is read by the barcode reader 31 and temporarily stored in the RAM 22. This identification code is printed in advance on a diagnostic chart prepared in advance for each vehicle. Instead of printing on the diagnostic chart, a bar code printed tag or sticker may be attached at a proper position on the vehicle body.

On the other hand, if it is determined in step S108 that the flag Fst = "0", that is, the power is turned on by the operator turning on the switch, in step S115, the operator selects the processing content. The menu screen is displayed on the display unit 27. Step S
At 116, the processing content selected by the operator on the menu screen is judged, and for example, when "vehicle diagnosis" is selected, the routine proceeds to step S109, and the diagnosis processing is started as in the case of the flag Fst = "1". It In addition, step S116
In, when the operator selects a process other than "vehicle diagnosis", the selected process is executed in step S117. In step S118, in step S11
In "6", it is determined whether "end" is selected,
If "end" is selected, the process ends.

As described above, in the present embodiment, the processing after power-on is changed depending on whether the power of the vehicle diagnostic device 2 is turned on or the cable connection is performed, and the power-on is connected by the cable. The diagnostic process starts immediately without displaying the menu screen. Therefore, the worker on the inspection line can automatically start the vehicle diagnosis simply by connecting the cable 5 of the vehicle diagnosis device 2 to each vehicle to be diagnosed that is conveyed one after another. Operation becomes easy. Further, when the vehicle diagnostic device 2 is activated by an operator turning on a switch, a menu screen is displayed, so that other processing can be easily selected.

FIG. 10 is a flowchart showing a diagnostic method of "vehicle speed sensor diagnostic" of diagnostic item 1 executed as step S200 of FIG. The "vehicle speed sensor diagnosis" is a diagnosis of whether or not the sensor for detecting the vehicle speed is functioning normally, and is based on the comparison result of the vehicle speed VS detected by the vehicle speed sensor and a reference value (reference vehicle speed VSref). It is diagnosed by an appropriate method.

In step S201, it is determined whether or not the vehicle speed sensor diagnosis is selected based on the diagnosis selection flag Fselc1 for "vehicle speed sensor diagnosis".
If lc1 = "0", it is determined that it is not selected and the process proceeds to the next diagnosis. If Fselc1 = "1", it is determined that it is selected and the process proceeds to step S202.

In step S202, it is determined whether or not the diagnosis has already passed, based on the pass flag Fpass1 relating to "vehicle speed sensor diagnosis". This flag "F
“Pass xx” indicates whether or not the diagnostic item xx has passed. If Fpass1 = “1”, it is determined that the test has already passed, and the next diagnosis is performed. If Fpass1 = “0”, It is determined that the test has not passed yet, and the process proceeds to step S203.

In step S203, the standard data storage area 73 of the ROM card 7 is used as one of the standard data.
The reference vehicle speed VSref stored in (FIG. 5) is read, and the current vehicle speed VS is detected via the ECU 1 in step S204. In step S205, the vehicle speed sensor diagnosis is executed based on the reference vehicle speed VSref and the vehicle speed VS. In step S206, in step S20
In step S207, it is determined whether or not the diagnosis executed is 5, and if the result is “pass”, the diagnosis pass flag Fpass1 is set to “1” (pass). If it fails, proceed to the next diagnosis. In step S208, the diagnostic item number "01" displayed on the display unit 27 is erased. FIG. 6B is a diagram showing a display example of the display unit 27 when only the “vehicle speed sensor diagnosis” has passed, and only the diagnosis item number “01” is deleted.

FIG. 11 is a flow chart showing a diagnosis method of "EGR diagnosis" of the diagnosis item 2 executed as step S300 of FIG. What is "EGR diagnosis"?
This is a diagnosis of whether or not a device (EGR) for recirculating exhaust gas to the combustion chamber of the engine to reduce NOx is functioning normally.

In steps S301 and S302, "EG
Based on the diagnosis selection flag Fselc2 and the diagnosis pass flag Fpass2 regarding "R diagnosis", it is determined whether or not the diagnosis item is selected and whether or not the diagnosis is successful, as described above. "EG
If "R diagnosis" is selected (Fselc2 = "1") and it has not passed (Fpass2 = "0"), step S303.
Then, the diagnosis of EGR is executed by an appropriate method. If it is determined in step S304 that the diagnosis has passed, "1" is set in the diagnosis pass flag Fpass2 in step S305, and the display unit 2 is set in step S306.
The diagnostic item number “02” displayed in 7 is deleted. If the diagnosis does not pass, the process goes to step S3.
The procedure proceeds from 04 to the next diagnosis.

12 and 13 show step S6 of FIG.
10 is a flowchart showing a diagnosis method of “Ne diagnosis” of diagnosis item 3 executed as 00. Figure 7 shows this "N
FIG. 3 is a functional block diagram of a vehicle diagnostic device that executes “e diagnosis”. "Ne diagnosis" is a diagnosis of whether the engine speed at idling is normal or not, and the engine speed Ne at idling and a reference value (allowable speed tolerance NID-TR
Diagnosis is based on the results of comparison with C).

Here, the structure of the vehicle diagnostic device will first be described with reference to the functional block diagram of FIG. 7, and then the specific operation thereof will be described with reference to the flowcharts of FIGS. It should be noted that the step numbers given in the blocks of FIG. 7 correspond to the step numbers in the flowchart, which means that the block executes the process of the step.

In FIG. 7, engine speed detecting means 4
28 is the CPU 2 that executes the processing of step S606
It is one function of 0 and communicates with the ECU 1 every time the “Ne diagnosis” is executed, and receives the engine speed Ne detected by the ECU 1. The engine load detection unit 429 is one function of the CPU 20 that executes the process of step S602. When the presence or absence of an engine load that affects the engine speed is detected by communicating with the ECU 1, the engine speed detected at the timing is The operation of the engine speed detecting means 428 is prohibited so that it is not used for diagnosis.

The engine speed integrating means 421 is one function of the CPU 20 for executing the processing of step S607.
Every time the "Ne diagnosis" is executed, the engine speed Ne detected by the engine speed detecting means 428 is integrated. The cumulative number storage unit 422 stores the step S605.
It is one function of the CPU 20 that executes the processing of (1), and stores the number of times Cmesu, which is the total number of engine revolutions. The average value calculation means 423 is a CP that executes the processing of step S612.
It is one function of U20, and is the integrated value Σ of the engine speed.
The average value of the engine speed is calculated based on Ne and the cumulative number Cmesu. The comparison means 424 is one function of the CPU 20 that executes the process of step S613, compares a reference value (non-standard data NID-ref) relating to the engine speed with the average value, and based on the comparison result, "Ne diagnosis". I do.

On the other hand, in step S601 of FIGS. 12 and 13, based on the selection flag Fselc3 and the pass flag Fpass3 relating to the diagnostic item 3, whether or not the diagnostic item is selected and whether or not the diagnostic is successful are determined and selected in the same manner as described above. F
selc3 = "1") and has not passed yet (Fpass3 =
If it is "0"), the process proceeds to step S602, and if not, the process proceeds to the next diagnosis.

In step S602, it is determined whether or not there is a load that occurs when the switch of the electric device is in the on state or the power steering is steering. "Ne diagnosis" is the detected idling speed N
If the difference between e and the target value is small, it is judged to be good, but if a load that affects the engine speed such as engine load or electrical equipment load is applied, the idling speed should be set higher than usual to compensate for this. Accurate diagnosis of idling speed becomes difficult because engine control is set to a higher value. Therefore, in the present embodiment, the presence / absence of a load is detected in advance in step S602 prior to the “Ne diagnosis”, and if the load is detected, the diagnosis is not performed, and step S602 is performed.
620 to a timer MID, which will be described later, and the cumulative number of times Cmesu,
After the variables such as the integrated value ΣNe are reset, the process proceeds to the next diagnosis, and if the load is not detected, the process proceeds to step S603.
In step S603, it is determined whether the idling is stable, and if it is not stable, the above step S6 is performed.
20. If it is stable, proceed to step S604.

When the idling is stable and the diagnosis start condition is satisfied as described above, the timer M is activated in step S604.
The operating state of the ID is judged, and if it has not started, it is started. In step S605, the cumulative number of times Cme
su is incremented. EC in step S606
Step S6: Receive engine speed Ne from U1
In 07, the engine speed Ne detected at the timing of this "Ne diagnosis" and the integrated value ΣNe up to the previous time are added. This added value is registered as a new integrated value ΣNe.

Then, in step S608 of FIG. 13, the timer MID is compared with the reference idling measurement time MID-ref which is one of the standard data. If the count value of the timer MID has reached the MID-ref, it is determined that the measurement period required for "Ne diagnosis" has already passed, and the process proceeds to step S609. In step S609, the idling diagnosis number CID is incremented each time, and in step S610, the diagnosis number CID is compared with the reference idling diagnosis number CID-ref which is one of the standard data.

When the number of times of diagnosis CID reaches the reference number of times of diagnosis CID-ref, it is determined that the number of times sufficient for diagnosis has been completed, and "0" is displayed on the display unit 27 in step S611.
The "0" display is erased. In step S612, the integrated value ΣNe of the engine speed Ne is added to the integrated number Cmesu.
The average value of the rotation speed Ne is calculated by dividing by.

In step S613, the absolute value of the difference between the average value of the rotation speed Ne and the non-standard data NID-ref is compared with the idling tolerance NID-TRC which is one of the standard data, and the absolute difference between the two is calculated. If the value is equal to or less than the tolerance NID-TRC, it is diagnosed that the idling is normal, and the process proceeds to step S614. If the absolute value of the difference between the two exceeds the tolerance NID-TRC, it is diagnosed that the idling is abnormal, and the step S
620, a timer MID, which will be described later, a cumulative number Cmesu,
After resetting variables such as the integrated value ΣNe, proceed to the next diagnosis. In step S614, the diagnostic pass flag Fpass3 related to the "Ne diagnostic" is set to "1", and in step S615, the diagnostic item number "03"("00" if displayed on the display unit 27 remains " 00 "and" 03 ") are erased.

As described above, according to this embodiment, the average value of the engine speed is calculated based on the integrated value ΣNe of the engine speed Ne which is repeatedly detected at each "Ne diagnosis" timing, and the average value is calculated. Diagnosis is made based on whether or not it is within the reference range. Therefore, even if "Ne diagnosis" is incorporated as one of the diagnostic items of the diagnostic method in which the diagnostics of a plurality of diagnostic items are cyclically repeated, accurate "Ne diagnostic" is possible, and various operations to be performed for each diagnostic item. Restrictions on order and timing can be reduced.

By the way, in the above-described embodiment, the reference value (non-standard data NID-ref) relating to the engine speed is a fixed value, and the diagnosis is performed only when the engine is in a no-load state. In a vehicle equipped with, because the engine speed during idling is finely controlled according to the instruction from the ECU according to the engine load, even if there is an engine load, the engine speed Ne at this time is indicated by the ECU. It is also possible to determine that the engine speed during idling is normal if it matches the set target value. Therefore, in the second embodiment of the present invention described below, "Ne diagnosis" is performed based on the result of comparison between the engine speed Ne and the target value instructed by the ECU without considering the engine load in the diagnosis.
I'm trying to do.

FIG. 17 is a functional block diagram of the second embodiment of the present invention, in which the same symbols as those used above represent the same or equivalent portions. 18 and 19 are flowcharts showing the operation. Since the same or equivalent processing is executed in the steps given the same reference numerals as above,
The description is omitted.

In this embodiment, E is set according to the engine load.
The target engine speed TNe determined by CU1 is set to "N
Each time "e-diagnosis" is performed, target rotation speed detection means 430, target rotation speed integration means 427 that integrates the detected target engine speed TNe, integrated value ΣTNe of the target engine speed TNe, and An average value calculating means 426 for calculating an average value of the target engine speed TNe on the basis of the number of times of diagnosis Cmesu is further provided, and the comparing means 424 compares the average values with each other, and "Ne diagnosis" is performed based on the comparison result. It is characterized in that it was done.

With such a configuration, when step S607 of FIG. 18 is completed, in step S621, the target rotation speed detecting means 430 causes the ECU 1 to set the target rotation speed TNe.
In step S622, the target rotation speed integration means 427 adds the target rotation speed TNe and the previous integrated value ΣTNe. The added value is the new integrated value ΣTN
Registered as e. This target rotation speed TNe is EUC1
Is the target idling speed that is determined according to the engine load.For example, when the engine is under load because the power steering is steering or the air conditioner is operating, It is set higher than the comparison. That is, the target rotation speed TNe is a variable value that changes according to the engine load at that time. Therefore, in the present embodiment, the integrated value ΣTNe is also obtained.

Thereafter, in step S623, the average value calculating means 426 calculates the average value of the target rotational speed TNe, and in step S613a, the absolute value of the difference between the average value of the rotational speed Ne and the average value of the target rotational speed TNe is calculated. Similar to the above, it is compared with the idling tolerance NID-TRC. If the absolute value of the difference between them is less than the tolerance NID-TRC, idling is diagnosed as normal and the routine proceeds to step S614.

According to this embodiment, it is possible to diagnose whether or not the engine speed matches the regular engine speed (target engine speed) even when the engine load is generated.

FIG. 14 is a flow chart showing a diagnostic method for diagnosing each switch system such as diagnostic items 4, 5, ... Executed as step S700 in FIG. If both the on state and the off state of the switch are detected, it is diagnosed as good.

In step S701, the diagnosis selection flag Fse for the "brake switch diagnosis" of the diagnosis item 4 is selected.
Based on lc4 and the diagnostic pass flag Fpass4, the presence or absence of selection of the diagnostic item and the success or failure of the diagnostic are determined in the same manner as described above. "Brake switch diagnosis" is selected (Fse
lc4 = "1") and has not yet passed (Fpass4 =
If it is "0"), the process proceeds to step S702. If not, the process proceeds to step S710 to execute the next switch diagnosis (diagnosis item 5). In step S702, a diagnosis regarding switch-on and switch-off is executed. In step S703, it is determined whether or not the above-mentioned diagnosis is successful, and if both the on-time and the off-time have passed, then in step S704, the diagnosis pass flag Fpass4 relating to the diagnosis is passed.
Is set to 1, and in step S705, the diagnostic item number “04” displayed on the display unit 27 is erased. Similarly, the same diagnosis is executed for the other switches, and the numbers of the passed diagnostic items are sequentially erased from the display unit 27.

FIG. 15 is a flow chart showing the operation of the "end processing" executed as step S800 in FIG. In step S501, as the current diagnosis result, for example, the number of the diagnosis item that has not passed the diagnosis is stored in the RAM 22 in association with the identification code of the vehicle read in step S114 of FIG. . Each time this step S501 is executed, this diagnosis result is rewritten at any time according to the diagnosis result at that time.

The RAM 22 shown in FIG. 1 can store the diagnosis results for a plurality of vehicles in association with the respective identification codes, and the diagnosis results for a plurality of vehicles (for example, 50-60 vehicles) can be stored. When collected, the operator automatically or manually selects the "transfer function" on the menu screen, and the diagnostic results are collectively transferred by wireless communication to the host device such as the host computer 30 via the transmission unit 24. To be done. In the host computer 30, the diagnostic results transferred for a plurality of units are collectively stored in the storage device 33, and when data for the planned number (for example, several hundreds) is accumulated,
This is stored in a portable storage medium such as an IC card or a floppy disk.

As described above, if the diagnostic results of each vehicle are managed collectively, not only the working efficiency of the operator is improved, but also the statistical processing of the diagnostic results is facilitated and the diagnostic results are analyzed. It also enables quick feedback to the production process.

In step S502 of FIG. 15, all diagnostic pass flags Fpassxx are referenced to determine whether all diagnostic items have passed. If all the diagnostic pass flags Fpassxx are set to "1", in step S503, the characters of "pass" are displayed large on the display unit 27 as shown in FIG. Notify the end of diagnosis. In step S504, it is determined whether or not the communication cable 5 is removed from the ECU 1, and if it is removed, it is turned off in step S505. If the communication cable 5 is not removed, in step S508, it is determined whether or not the key operation for turning off the power supply is performed by the operator. When the key operation is performed, the process proceeds to step S505. If the key operation has not been performed, the process returns to step S503.

On the other hand, if it is determined in step S502 that the diagnostic item 2 does not pass, the process goes to step S506. At this time, since the display "02" remains on the display unit 27 as shown in FIG. 6 (c), the operator can easily recognize that only the diagnostic item 2 has not yet passed. it can.

Further, as shown in FIGS. 6 (d) and 6 (e),
When the diagnosis item number “03” of “Ne diagnosis” remains, the validity of the diagnosis result of the diagnosis item 3 is determined depending on whether the display “00” remains. That is, as described with respect to steps S610 and S611 in FIG. 13, the display "00" indicates that the prerequisite of diagnostic item 3 (for example, the engine is sufficiently warm and there is no load) is satisfied. The number of times the diagnosis was made (ie CI
D) is erased when the number of times exceeds a predetermined number (CID> CID-ref). Therefore, as shown in FIG. 7D, when the display "00" also remains, it means that the precondition of the diagnosis item 3 is not satisfied and the diagnosis itself has not been started yet. Therefore, the operator does not immediately judge that the diagnosis item 3 is defective, but thereafter, if the Ne diagnosis is performed again and the displays "00" and "03" are erased, it is judged as good.

If the display "00" disappears, the precondition of the diagnostic item 3 is satisfied and the number of times is sufficient (that is, C
Since it has not passed even though the diagnosis of (ID) is performed, the worker immediately determines that the diagnosis item 3 is defective.

As described above, in the present embodiment, with respect to the diagnostic items that need to satisfy the preconditions before the diagnosis, the failure code "00" indicating whether or not the preconditions are satisfied is displayed. Therefore, even if the diagnosis of the relevant diagnostic item has not passed, it can be easily recognized that this is due to the failure of the precondition, and a diagnostic item that is not necessarily defective is erroneously determined as defective. There is no end.

In step S506, it is determined whether or not the switch operation for turning off the power supply is performed by the operator. When the switch operation is performed, the process proceeds to step S505, and the switch is turned off. If not performed, it is determined in step S507 whether the communication cable 5 has been removed from the ECU 1. When the communication cable 5 is removed, the step S
The process proceeds to step 505 to be in the off state, and if not removed, the process proceeds to the next diagnosis in order to continue the diagnosis.

FIG. 16 is a flow chart showing the operation of the "standby mode process" executed as step S900 in FIG. In step S901, it is determined whether or not the standby mode is in progress. Since the diagnosis mode is initially set, the flow advances to step S902. In step S902, the engine speed Ne-pre detected last time and the engine speed Ne detected this time are compared. Here, during the diagnosis work, that is, when the engine is rotating, the engine speed slightly changes even in the idling state. Therefore, it is determined that they do not match, and the process proceeds to step S903. In step S903, the standby mode timer Tss is reset, and in the following step S904, the engine speed Ne detected this time is newly registered as the previous engine speed Ne-pre, and the routine proceeds to the next diagnosis.

Thereafter, if the diagnosis work is interrupted and the engine is stopped, for example, during a break, the above-mentioned step S902
In, it is determined that the previous engine speed Ne-pre and the current engine speed Ne match, so the process proceeds to step S905. In step S905, it is determined whether or not the timer Tss has been started. Since it is initially determined that the timer Tss has not been started, the process proceeds to step S906, in which the timer Tss is started.

When the standby mode timer Tss is started as described above, the determination at step S905 is affirmative thereafter, and therefore the process proceeds from step S905 to step S907. In step S907, the count value of the timer Tss is compared with the standby mode starting condition Tss-ref which is one of the standard data. When the count value of the timer Tss exceeds the starting condition Tss-ref, step S90
In 8, the operation mode of the process shifts from the diagnostic mode to the standby mode, and the backlight of the display unit 27 and its liquid crystal drive are both turned off. Further, the diagnosis progress up to this point is temporarily stored in the RAM 22.

When the standby mode is started, the next process proceeds from step S901 to step S909, and the previous engine speed Ne-pre and the current engine speed Ne are compared. During the break time, the two are always in agreement and the determination in step S909 is positive, so the standby mode is maintained, but when the break time ends and the engine is restarted,
If the determination in step S909 is negative, step S91
Go to 0. In step S910, the operation mode of the process shifts from the standby mode to the diagnostic mode, and the backlight of the display unit 27 and the liquid crystal drive are both turned on. At the same time, the progress of diagnosis until the standby mode is started is read from the RAM 22, and the display contents just before the start of the standby mode are reproduced on the display unit 27. In step S911, the engine speed Ne detected this time is newly registered as the previous engine speed Ne-pre, and then the process returns to the "vehicle speed sensor diagnosis" described with reference to FIG. Is cyclically repeated as shown in FIG.

As described above, in the present embodiment, the shift from the diagnostic mode to the standby mode is automatically performed when the change in the engine speed is no longer detected, and the shift from the standby mode to the diagnostic mode is the change in the engine speed. Is detected automatically. Therefore, the worker only has to stop the engine when the rest time starts and interrupts the diagnosis, and restarts the engine when the rest time ends and restarts the diagnosis, and no other special operation is required. . Therefore, the operator is not burdened with an extra burden when shifting from the diagnostic mode to the standby mode and from the standby mode to the diagnostic mode.

In the present embodiment, the operator operates the brake pedal from the time when the operator starts one operation for each diagnosis until the operation is completed, for example, in the case of the "brake switch diagnosis". The "brake switch diagnosis" must be executed during (depressing). Therefore,
The diagnosis of each diagnostic item should be cyclically and repeatedly executed at such a speed that the diagnosis of all diagnostic items is executed at least once between the time when the operator starts one operation and the time when the operation is completed. Is desirable.

As described above, according to such a diagnosis method, when the operator performs a predetermined operation for each item to be diagnosed, the operator is not restricted with respect to the order or timing. Therefore, the degree of freedom regarding the order and timing of operations is increased, and efficient vehicle diagnosis can be performed in a short time.

Further, in the above-mentioned embodiment, all the diagnostic item numbers are first displayed in a list, the numbers of the passed diagnostic items are sequentially deleted, and the diagnostic items with the remaining numbers are judged to be defective. However, conversely, it is also possible to sequentially display the numbers of the diagnostic items that have passed and judge the diagnostic items with the numbers that are not displayed until the end as defective. Similarly, the display "00" is also described as being erased when the diagnosis of the diagnosis item 3 is sufficiently performed, but conversely, the display "00" is not deleted when the diagnosis of the diagnosis item 3 is sufficiently performed. It may be displayed.

Further, although the case where the vehicle diagnosis method and apparatus of the present invention is used in the "inspection step" in a factory production line has been described as an example, the present invention is not limited to this and a repair factory or The same can be applied to the vehicle diagnosis method and device used in other environments.

[0082]

As described above, according to the present invention, "Ne
Each time "Diagnosis" is repeatedly executed, the detected values of the engine speed are integrated, and the average value of the engine speed is calculated based on the integrated value. Therefore, even if "Ne diagnosis" is incorporated as one of the diagnostic items of the diagnostic method in which the diagnostics of a plurality of diagnostic items are cyclically repeated, there are less restrictions on the order and timing of various operations to be performed for each diagnostic item.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an ECU 1 and a vehicle diagnostic device 2 of the present invention mounted on a vehicle to be diagnosed.

FIG. 2 is a diagram schematically showing the stored contents of a ROM card 7.

FIG. 3 is a diagram showing stored contents of a diagnostic item management table 71.

FIG. 4 is a diagram showing stored contents of a nonstandard data storage area 74.

FIG. 5 is a diagram showing stored contents of a standard data storage area 73.

FIG. 6 is a diagram showing a display example on a display unit 27.

FIG. 7 is a functional block diagram of the vehicle diagnostic device according to the first embodiment of the present invention.

FIG. 8 is a flowchart showing an outline of vehicle diagnosis according to the present invention.

FIG. 9 is a flowchart showing an operation of initial processing.

FIG. 10 is a flowchart showing an operation of vehicle speed sensor diagnosis.

FIG. 11 is a flowchart showing the operation of EGR diagnosis.

FIG. 12 is a flowchart showing an operation of Ne diagnosis.

FIG. 13 is a flowchart showing an operation (continuation) of Ne diagnosis.

FIG. 14 is a flowchart showing an operation of each switch diagnosis.

FIG. 15 is a flowchart showing an operation of end processing.

FIG. 16 is a flowchart showing an operation of a standby mode process.

FIG. 17 is a functional block diagram of a second embodiment of the present invention.

FIG. 18 is a flowchart showing another operation of Ne diagnosis.

FIG. 19 is a flowchart showing another operation (continuation) of Ne diagnosis.

[Explanation of symbols]

1 ... ECU, 2 ... Vehicle diagnostic device, 3 ... Actuator,
4 ... Sensor, 5 ... Communication cable, 7 ... ROM card, 1
6, 17, 18 ... Connector, 20 ... CPU, 24 ... Transmission unit, 27 ... Display unit

─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-62-258831 (JP, A) JP-A-6-50852 (JP, A) JP-A-6-58846 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) G01M 17/007 G01M 15/00

Claims (4)

(57) [Claims] 1. A vehicle diagnostic device for diagnosing a plurality of types of items based on various data obtained from an on-vehicle electronic control unit via a communication means, and cyclically performs a plurality of types of diagnostics including engine speed diagnosis. Circulation diagnostic means that repeatedly executes and determines the quality of each diagnosis , engine speed detection means that detects the engine speed for each engine speed diagnosis , and engine speed detected by the engine speed diagnosis this time.
Is detected by each engine speed diagnosis up to the previous time and integrated
Engine rotation speed integration means for adding to the calculated integration value, integration frequency storage means for storing the integration frequency of the engine speed, and an average value of the engine speed based on the integration value of the engine speed and the integration frequency. And an average value calculation means for calculating the average value and the reference value are compared, and the relationship between them is determined by a predetermined condition.
When the conditions are satisfied, the engine speed diagnosis is passed.
Vehicle diagnostic apparatus characterized by comprising a comparison means that. 2. An engine load detecting means for detecting the presence or absence of an engine load that affects the engine speed, wherein when the engine load is detected, the engine speed detected at the timing is used for diagnosis. The vehicle diagnostic device according to claim 1, wherein the vehicle diagnostic device is not provided. 3. A vehicle diagnostic device for diagnosing a plurality of types of items based on various data obtained from a vehicle-mounted electronic control unit via a communication means, and cyclically performs a plurality of types of diagnosis including engine speed diagnosis. Circulation diagnostic means that repeatedly executes and determines the quality of each diagnosis , engine speed detection means that detects the engine speed for each engine speed diagnosis , and engine speed detected by the engine speed diagnosis this time.
Is detected and accumulated in each engine speed diagnosis before the previous time.
Engine speed integrating means for adding to the calculated integrated value, and target engine speed detecting means for detecting the target engine speed determined by the on-vehicle electronic control device according to the engine load each time the engine speed is detected. A target revolution number accumulating unit that accumulates the target engine revolution number, an accumulated number storage unit that stores the accumulated number of engine revolutions, and an engine revolution based on the accumulated value of the engine revolutions and the accumulated number. A first average value calculating means for calculating an average value of the engine speed, and a second average value calculating means for calculating an average value of the target engine speed based on the integrated value of the target engine speed and the number of times of integration. , The above average values are compared , and the relationship between the two satisfies the specified conditions.
When you do, a comparison hand that passes the engine speed diagnosis
A vehicle diagnostic device comprising: a step . 4. The vehicle diagnostic device according to claim 1, wherein the engine speed diagnosis is performed in a stable idling state.