JP2000311539A - Failure diagnostic device for on-vehicle switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize cost reduction and enhance the determination accuracy in failure diagnosis. SOLUTION: If any of switches SW11 to SW33 is in an on state although the outputting is stopped of drive signals from a SW-input determination part 13 to a switch group 11, such a state is detected by a SW diagnosis/ determination part 14, and thus a failure determination part 15 recognizes that the switch is out of order. The state of failure, such as electric leakage and wiring short circuit, of the switches SW11 to SW33 is detected easily, inexpensively, and accurately, by simple logical determination.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-vehicle switch failure diagnosis apparatus for detecting an abnormality of a switch for controlling the drive of a load side unit.

[0002]

2. Description of the Related Art In recent years, various electronic devices have been mounted in the field of automobiles due to the development of electronic technology, and accordingly, the number of mounted switches for vehicles has generally increased. . Then, it is required that the failure diagnosis of the plurality of switches be performed by using a microcomputer chip having a small number of ports to efficiently perform the failure diagnosis while configuring the hardware at low cost.

Specifically, as shown in FIG. 6, a plurality of switches SW11 to SW33 are arranged in a matrix, and a plurality of switches SW in the matrixed switch group 1 are arranged.
11 to one terminal of SW33 are connected to a small number of row lines 2a to 2
c to connect to the input terminals IN1 to IN3 of the microcomputer chip 3 and switch S
The other terminals of W11 to SW33 are connected to a small number of column lines 4a to
4c, common connection is performed to output terminals OUT1 to OUT3 of the microcomputer chip 3.
With such a configuration, even if the number of ports of the microcomputer chip 3 is small, it is possible to diagnose failures of more switches SW11 to SW33.

In a conventional on-board switch failure diagnostic device using a microcomputer chip, a diagnostician pushes and operates any one of the switches SW11 to SW33, for example, at a regular timing every 5 ms. Multiple output terminals O from computer chip 3
ON signals are sequentially transmitted to the column lines 4a to 4c with a time difference through the UT1 to OUT3, and the input terminal IN1 at this time is transmitted.
By reading the input levels to .about.IN3, any of the switches SW11 to SW pressed and operated by the diagnostician
It is determined whether or not 33 is switched on. In this case, the microcomputer chip 3
Merely determines the state of each of the switches SW11 to SW33 immediately after outputting the ON signal through the output terminals OUT1 to OUT3. When the ON signal is not output from the output terminals OUT1 to OUT3, the input terminals IN1 to I1
The determination of the input state of N3 was not performed.

[0005]

In the conventional method, as described above, when the ON signals are not output from the output terminals OUT1 to OUT3, the input states of the input terminals IN1 to IN3 are not determined. Since the change in the state before and after the operation of pressing the switches SW11 to SW33 by the diagnostician is not detected, for example, some abnormality occurs in the row lines IN1 to IN3 as the input lines and the switches are electrically turned on. If the signal remains, the microcomputer chip 3 erroneously recognizes that the switches SW11 to SW33 have been pressed even though the pressing operation has not been performed. It cannot be determined whether the row lines IN1 to IN3 are normal or abnormal.

In such a state, if the product is shipped without detecting the abnormality, for example, the air conditioner or the audio may start to operate at its actual use.

[0007] If the product is transported to a service factory due to this failure, the cause of the failure (water, garbage) at the time of failure diagnosis.
In some cases, an abnormal situation cannot be reproduced because the environment has changed since the occurrence of the failure, and the cause cannot be determined. If prospective repair is performed in such a state and returned to the user without repairing the essential failure, the failure may recur when used on the user side.

It is an object of the present invention to provide an in-vehicle switch failure diagnosis device which is inexpensive and can improve the accuracy of determination in failure diagnosis.

[0009]

In order to solve the above problems,
The invention according to claim 1 is an on-vehicle switch failure diagnosis device that detects an abnormality of a switch for performing drive control of a load-side unit, and supplies a predetermined drive signal to the switch to turn on / off the switch. A switch input determining unit that detects a state; a switch diagnostic determining unit that detects an on / off state of the switch when the switch input determining unit stops the drive signal; A failure determination unit that recognizes a failure state when the switch input determination unit has stopped outputting a drive signal, the switch diagnosis determination unit is equivalent to an on-state of the switch. When detecting a voltage level, the failure determination unit has a function of outputting information about the switch in the ON state, Serial failure determination unit, when the said switch diagnosis determination unit has received information about the switch of the ON state and the same voltage level, and has a function of recognizing as there is a fault in the switch.

According to a second aspect of the present invention, a plurality of the switches are provided, and the switches are connected in a matrix by a plurality of column lines and a plurality of row lines. Having a function of outputting the drive signal to the plurality of switches through one of the line groups. The switch diagnosis determination unit detects a voltage level of the other line group of the column line and the row line. The other line group has a function of outputting information of a plurality of switches connected to a line having a voltage level equivalent to the ON state to the failure determination unit, and the failure determination unit performs the switch diagnosis determination. When the information on the plurality of switches is obtained from the unit, all of the plurality of switches are recognized as being in a failure state and recognized.

According to a third aspect of the present invention, when the failure determination unit recognizes a switch in a failure state, the failure determination unit further includes a diagnosis recording unit that records abnormality information including the switch in the failure state and the failure occurrence time. Things.

According to a fourth aspect of the present invention, when the failure determination unit recognizes a switch in a failure state, the switch function switching is performed so as to substitute another switch in a normal state in place of the switch in the failure state. Unit.

According to a fifth aspect of the present invention, in the multiplex communication unit, when the failure determination unit recognizes a switch in a failure state, an abnormality notification is sent to a load-side unit provided corresponding to the switch in the failure state. Is further provided.

[0014]

FIG. 1 is a diagram showing an on-vehicle switch failure diagnosis apparatus according to one embodiment of the present invention. FIG.
As described above, the in-vehicle switch failure diagnosis device 10 diagnoses a failure of the switch group 11 in which a plurality of push-button switches SW11 to SW33 for driving and controlling a predetermined load side unit HU are arranged in a matrix. Switch SW11 in the switch group 11
~ SW33, when the switch signal is pressed, the output voltage level from each of the switches SW11 to SW33 is detected in both the state where the drive signal is supplied to the switch group 11 and the state where the drive signal is not supplied, so that the failure diagnosis can be performed with high accuracy. Is performed.

More specifically, the on-vehicle switch failure diagnosis apparatus 10 according to the present embodiment includes a multiplex communication unit 12 for performing multiplex communication with a plurality of load-side units (vehicle electronic devices) HU.
A switch input determining unit (SW input determining unit) 13 that supplies a drive signal to the switch group 11 and detects an output voltage level from the switch group 11, and that the switch input determining unit 13 stops the drive signal. A switch diagnostic determining unit (SW diagnostic determining unit) 14 for detecting an output voltage level from the switch group 11 and a switch input determining unit 13
And a failure determination unit 15 that recognizes a failure state when an abnormality is found in at least one of the switch diagnosis determination unit 14
And a switch function switching unit 16 that, when a failure is recognized by the failure determination unit 15, switches to use another normal switch SW11 to SW33 in place of one of the switches SW11 to SW33 in the failure state. A diagnosis recording unit 17 for recording, as a diagnosis code, the fact that the switch group 11 is abnormal in the event that there is an error.

The multiplex communication unit 12 has a function of notifying the load side unit HU of an abnormality when the failure judgment unit 15 judges a failure. The HU performs a fail-safe process such as stopping driving, and, when the switch function is switched to the substitute switch side in the event of a switch failure as described later, notifies the load-side unit HU relating to the failed switch to that effect. It has become.

A general microcomputer chip 20 having a CPU, a ROM, a RAM, and the like is used for the switch input determination unit 13, the switch diagnosis determination unit 14, and the failure determination unit 15, and all the arithmetic operations are stored in the ROM or the like in advance. It is to be executed by software that has been created.

Here, the microcomputer chip 20
Is connected to a first column line 21a to which one terminal of a plurality of switches SW31 to SW33 in the third column of the switch group 11 is commonly connected, and to the second output terminal OUT2. , A second column line 21b to which one terminal of the plurality of switches SW21 to SW23 in the second column of the switch group 11 is connected in common, and a third output terminal OUT3 is connected to the first column of the switch group 11 in the first column. A third column line 21c to which one terminal of a plurality of switches SW11 to SW13 of the eye is commonly connected is connected. A plurality of switches SW1 in the first row of the switch group 11 are connected to the first input terminal IN1 of the microcomputer chip 20.
The first row line 22a to which the other terminals of the first to SW31 are commonly connected is connected, and a plurality of switches SW12 to SW of the second row of the switch group 11 are connected to the second input terminal IN2.
The second row line 22 to which the other terminal of the line 32 is connected in common
b is connected, and a switch group 1 is connected to the third input terminal IN3.
The third row line 22c to which the other terminals of the plurality of switches SW13 to SW33 in the first third row are commonly connected is connected.

The switch input judging section 13 in the microcomputer chip 20 has a plurality of output terminals OUT1 to OU.
Through T3, each column line 21a-2 of the switch group 11
1c, the drive signals are sequentially output to each of them, and in synchronization with this, the ON / OFF state of each of the switches SW11 to SW33 of the switch group 11 through the row lines 22a to 22c connected to the plurality of input terminals IN1 to IN3. Is detected. The detection result is displayed on the display unit 23 of the light emitting element array or the like to notify the switches SW11 to SW33 that have been turned on. When the diagnostician detects a failure state, the input operation unit 24 can input which of the switches SW11 to SW33 has failed. Also,
The switch input determination unit 13 includes output terminals OUT1 to OUT
When the drive signal from 3 is stopped, the fact is immediately transmitted to the switch diagnosis determination unit 14.

When the switch input determining unit 13 stops driving signals from the output terminals OUT1 to OUT3, the switch diagnostic determining unit 14 determines whether the plurality of input terminals IN1 to IN1 are inactive.
ON / OFF of the switches SW11 to SW33 of the switch group 11 through the row lines 22a to 22c connected to IN3.
The off state is detected, and any of the row lines 22a to 22c is detected.
When the switches SW11 to SW33 connected to the second line are at the same voltage level as the ON state due to a wiring short with another path, etc.
, Outputs the information of the switches SW11 to SW33 connected to the failure determination unit 15.

The failure determination unit 15 includes switches SW11 to SW which are input when an input is received from the input operation unit 24.
The switches SW11 to SW3, which have a function of recognizing that there is a failure in the switch 33 and have been recognized by the switch diagnosis determination unit 14 to have a voltage level equivalent to the ON state
3 has a function of recognizing that there is an electric leakage or a wiring short with another route.

The switch function switching unit 16 includes
Switches SW11 to SW33 related to the failure determined in 5
Is disabled and other switches are enabled. That is, the switch SW1 in the failure state by the input operation unit 24
1 to SW33, the switches SW11 to SW33 are set to other switches SW11 to SW3.
Switch to 3. Further, the switches SW11 to S of any of the row lines 22a to 22c are determined by the switch diagnosis determination unit 14.
If W33 is in a fault state, its row line 22a
To all switches SW11 to S connected to
W33 is invalidated, and the switches SW11 to SW33 connected to the other row lines 22a to 22c are used as substitute switches. Specifically, for example, the plurality of switches SW1 in the third row connected to the third row line 22c
3 to SW33 are prepared as surplus substitute switches that are not used in the initial state, and the switches SW11 in the first row are prepared.
To SW31 and any of the switches SW12 to SW32 in the second row, a substitute switch SW1 is used instead of the switches SW11 to SW32 in the failed row.
3 to switch to use SW33. The timing at which the switching function of the switch function switching unit 16 is performed is desirably performed based on a switching instruction input from an external switch or the input operation unit 24. still,
As a specific switching function switching method, for example, a wiring connection switching circuit using a transistor or the like is provided as the switching function switching unit 16 so that the connection relationship between the switch group 11 and the load side unit HU is switched. I just need.

The diagnosis recording unit 17 uses a rewritable nonvolatile memory such as a flash ROM. When a failure is detected by the failure determination unit 15, the failed switches SW11 to SW33 are replaced. Various information such as switch identification information for identification and a failure occurrence start time and a failure occurrence end time are recorded.

The on-board switch failure diagnosis apparatus 10 is designed to start a switch failure diagnosis operation by operating a predetermined diagnosis start switch or the like of the on-vehicle switch failure diagnosis apparatus 10 (not shown).

In-vehicle switch failure diagnosis apparatus 10 having the above configuration
Will be described. Here, as the switch group 11, for example, a center cluster integration switch having an audio switch, an air conditioner switch, and the like in a matrix configuration will be described as an example. The switch group 11 such as the audio switch and the air conditioner switch is connected to a load unit HU such as a clock 31, an audio device 33, and an air conditioner 33 via a multiplex communication bus 30 as shown in FIG. .

First, by operating a predetermined diagnosis start switch or the like of the on-vehicle switch failure diagnosis device 10 (not shown),
The switch failure diagnosis operation is started. The switch input determination unit 13 outputs a drive signal to the switch group 11 through the column lines 21a to 21c while sequentially switching the output terminals OUT1 to OUT3 as shown in (1) to (3) in FIG. Then, in synchronization with this, (4) in FIG.
As shown in (6) to (6), the switch input determination unit 13 includes the row lines 22a to 22a connected to the plurality of input terminals IN1 to IN3.
2c, each switch SW11-S of the switch group 11
The on / off state of W33 is detected.

FIG. 2 shows an example in which the switch SW12 is depressed, and only when the drive signal is output to the third column line 21c through the third output terminal OUT3, the second row to which the switch SW12 is connected. Line 22b
Is turned on, and this state is transmitted to the switch input determination unit 13 through the input terminal IN2. In other cases, the off state is transmitted to each of the input terminals IN1 to IN3. As for the on / off state of the switch SW12, lighting display or the like is performed on the display unit 23 such as the light emitting element array.

Here, regardless of whether the drive signal is on or off, the audio device 32 is not affected by the attachment of dust and water droplets.
It is assumed that an abnormal situation has occurred in which switches such as the tune-down switch and the time reset of the clock 31 remain on. FIG. 3 shows that in such a case, an abnormality such as leakage or short-circuit of a wiring to another path occurs in any of the switches SW12 to SW32 in the second row, and the voltage of the second row line 22b is equivalent to the ON state. It is a figure showing the case where it has been held at the level. In this case, not only when a drive signal is output from the third output terminal OUT3 to the third column line 21c ((3) in FIG. 3), but also when a drive signal is output to the other column lines 21a and 21b (see FIG. 3 (1) and (2)), the second row line 22b is maintained at the same voltage level as the ON state ((5) in FIG. 3). As for the on / off state of the switch SW12, lighting display or the like is performed on the display unit 23 such as the light emitting element array. In this case, the diagnostician looks at the lighting display or the like of the display unit 23 and
Despite pressing only one of the switches SW11 to SW33, the plurality of switches SW11
It can be easily known that it is determined that .about.SW33 is in the ON state. That is, the diagnostician can determine that an abnormality has occurred in the switches SW12 to SW32 connected to the second row line 22b.
~ SW32 can be determined to be faulty. When it is determined that a failure has occurred, the switches SW11 to SW33 relating to the failure are input to the failure determination unit 15 through the input operation unit 24.

Next, when the switch input judging section 13 stops driving signals from the output terminals OUT1 to OUT3, the fact is immediately transmitted to the switch diagnosis judging section 14. Immediately thereafter, in the switch diagnosis determination unit 14, while the drive signals from the output terminals OUT1 to OUT3 are stopped, each switch of the switch group 11 is switched through the row lines 22a to 22c connected to the plurality of input terminals IN1 to IN3. An on / off state of SW11 to SW33 is detected. In this case, any of the row lines 22a to 22
The off state should also be maintained for the second row line 22b. For example, as shown in FIG. Is detected while the voltage level equivalent to the ON state is held. Therefore, the switch diagnosis determination unit 14 can automatically and easily detect an abnormal situation on the second row line 22b.

As described above, the failure determination unit 15 determines whether there is an input from the input operation unit 24 or whether any one of the row lines 22 is detected by the switch diagnosis determination unit 14.
When it is detected that there is an abnormality in any of the switches SW11 to SW11 of the row line 22a to 22c.
It recognizes that the SW 33 has a leakage or a short circuit. The determination operation at this time is shown in Table 1 below.

[0031]

[Table 1]

Here, any of the switches SW11 to S
When W33 is not pressed, both the detection by the switch input determination unit 13 and the detection by the switch diagnosis determination unit 14 are in the “OFF” state (the first row in Table 1).

Any of the switches SW11 to SW
When the button 33 is pressed, the switch input determination unit 13
In the detection of the switches SW11 to S
Only W33 is turned “ON”, and the switch diagnosis determination unit 14
Then, all the switches SW11 to SW33 are in the “OFF” state (second row in Table 1).

In these cases, the switches SW11 to SW11
Since it can be determined that the SW 33 is operating normally, the failure determination in the failure determination unit 15 is “OK (normal state)”.

On the other hand, irrespective of whether the switches SW11 to SW33 are pressed or not, if any one of the switches SW11 to SW33 is held in the ON state due to a short circuit or the like, the detection by the switch input determination unit 13 and the switch diagnosis determination are performed. Part 1
4 remains in the “on” state (Table 1).
The third line in the middle). This state is particularly caused by the switch diagnosis determination unit 1.
4 is "ON" (a voltage level equivalent to the ON state of the switches SW11 to SW33), which should be in the "OFF" state. Therefore, it is determined that an abnormal situation has occurred. The failure judgment is "N
G (failure state) ".

The recognition result is transmitted to the multiplex communication unit 1
2, transmitted to the switch function switching unit 16 and the diagnosis recording unit 17;

In the multiplex communication unit 12, when the failure determination unit 15 determines a failure, the multiplex communication unit 12 notifies the load side unit HU of an abnormality. When receiving an abnormality notification from the multiplex communication unit 12, the load-side unit HU performs a fail-safe process such as suspension of driving. As a result, the load side units HU such as the clock 31, the audio device 32, and the air conditioner 33 do not immediately receive the tune-down switch, the clock reset switch, and the like in the switch group 11.
That is, for example, in the audio device 32 in FIG.
The currently executed tune-down operation or the like is temporarily stopped. Regarding the clock 31, the operation of the communication transmitted immediately before (about one minute before) is canceled and the operation returns to the original state.

The switch function switching unit 16 preferably switches the switches SW11 to SW15 based on the failure based on a switching instruction input from an external switch or the input operation unit 24.
SW33 is invalidated, and the other switches SW11 to SW33 are disabled.
Is switched to be used as a substitute switch. For example, a plurality of switches SW13 to SW33 in the third row connected to the third row line 22c are prepared as surplus surplus switches that are not used in the initial state, and the switches SW11 to SW31 in the first row and the Second-line switch SW12
If a failure has occurred in any of the switches SW13 to SW32, the switches are switched to use the substitute switches SW13 to SW33 instead of the switches SW11 to SW32 in the failed row. Therefore, as an emergency measure, the user replaces the failed switches SW11 to SW33 with another switch SW.
11 to SW33 can be used instead.

In the diagnosis recording unit 17, as shown in FIG.
Various information such as switch identification information for identifying the SW 33 and a failure occurrence start time and a failure occurrence end time are recorded. This makes it possible to easily obtain detailed information on the occurrence cycle and the occurrence date of the failure at a later time. For example, if the information is read out from the diagnosis recording unit 17 using a predetermined information reading tool or the like at the time of repair at a service factory. Useful information useful for repair can be easily obtained.

As described above, when the switches SW11 to SW33 are at the same voltage level as the ON state even though the drive signal is in the OFF state, such an abnormal situation is automatically and automatically performed by the switch diagnosis determination unit 14. Since it can be easily detected, it is possible to easily and accurately detect the abnormality of the switches SW11 to SW33 while minimizing the cost increase as compared with the conventional example.

When the input switch information is abnormal based on the abnormality information, the multiplex communication unit 12 sends the failed switch HU to the load-side unit HU, which has been once disabled. Instead, the substitute switch is notified that the switch function has been switched. In response to the notification, the load-side unit HU receives control by the newly switched substitute switch. As a result, fail-safe processing can be easily performed.
Unintended operations by the operator can be avoided, which can greatly contribute to the safety and reliability of the vehicle.

In this embodiment, the on / off state of the switches SW11 to SW33 is displayed on the display unit 23. However, the diagnosis by the switch diagnosis determination unit 14 alone is sufficient for each row line 22a to 22c. If the abnormal situation can be detected, the display unit 23 and the input operation unit 24 may be omitted, and the failure determination in the failure determination unit 15 may be performed only depending on the determination result in the switch diagnosis determination unit 14. Absent.

[0043]

According to the first aspect of the present invention, when the output of the drive signal to the switch is stopped and the switch is at the same voltage level as the ON state, the switch diagnosis is performed. Since the failure is detected by the determination unit and the failure determination unit recognizes that the switch has a failure, a failure state such as a switch leakage or a wiring short circuit can be detected by a simple logical determination.
A switch failure can be accurately detected without increasing the cost.

According to the second aspect of the present invention, by connecting a plurality of switches in a matrix, an on-vehicle switch failure diagnosis device can be configured using a microcomputer chip having a small number of ports, and is inexpensive. It is possible to perform accurate failure detection with a simple hardware configuration.

According to the third aspect of the invention, when the failure determination unit recognizes the switch in the failure state, the failure information including the switch in the failure state and the failure occurrence time is recorded in the diagnosis recording unit. Since detailed information on the cycle and date of occurrence of failure can be easily obtained later, for example, it can be read out from the diagnosis recorder using a predetermined information reading tool at the time of repair at a service factory. Thus, useful information useful for repair can be easily obtained.

According to the fourth aspect of the present invention, when the failure judging unit recognizes the switch in the failure state, the switch function is such that the switch in the normal state is substituted for the switch in the failure state. Since switching is performed by the switching unit, even when a switch related to each load-side unit fails, drive control of each load-side unit can be executed without delay.

According to the fifth aspect of the present invention, when the failure determination unit recognizes the switch in the failure state, the multiplex communication unit sends the load-side unit provided corresponding to the switch in the failure state to the load-side unit. Since the failure notification is performed, if the load-side unit performs a fail-safe process such as not performing the process when the switch fails, the operation of the load-side unit that the operator does not intend can be performed. It is possible to avoid a situation in which the vehicle is executed without permission, which can greatly contribute to the safety and reliability of the vehicle.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an on-vehicle switch failure diagnosis device according to one embodiment of the present invention.

FIG. 2 is a timing chart showing a state of each signal when a switch is normal.

FIG. 3 is a timing chart showing the state of each signal when any of the switches on the second row has a failure.

FIG. 4 is a block diagram showing a state in which a switch group, a vehicle-mounted switch failure diagnosis device, and each load-side unit are connected via a multiplex communication bus.

FIG. 5 is a diagram showing information recorded in a diagnosis recording unit.

FIG. 6 is a block diagram showing a conventional in-vehicle switch failure diagnosis device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 On-vehicle switch failure diagnostic device 11 Switch group 12 Multiplex communication unit 13 Switch input determination unit 14 Switch diagnosis determination unit 15 Failure determination unit 16 Switch function switching unit 17 Diagnosis recording unit 20 Microcomputer chips 21a to 21c Column lines 22a to 22c rows Line 23 display unit 24 input operation unit 30 multiplex communication bus 31 clock 32 audio device 33 audio device HU load side unit IN1 to IN3 input terminal OUT1 to OUT3 output terminal SW11 to SW33 switch

 ──────────────────────────────────────────────────続 き Continued on the front page (71) Applicant 000003207 Toyota Motor Corporation 1 Toyota Town, Toyota City, Aichi Prefecture (72) Inventor Toshiyuki Sonoda 1-7-10 Kikuzumi, Minami-ku, Nagoya City, Aichi Prefecture Harness Integrated Technology Co., Ltd. Inside the laboratory (72) Inventor Isao Isshiki 1-7-10 Kikuzumi, Minami-ku, Nagoya City, Aichi Prefecture Inside Harness Research Institute, Inc. (72) Inventor Kazuhiko Nakajima 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 5G034 AC02

Claims (5)

[Claims] 1. An on-vehicle switch failure diagnosis device for detecting an abnormality of a switch for controlling a drive of a load side unit, wherein a predetermined drive signal is supplied to the switch to detect an on / off state of the switch. A switch input determination unit, a switch diagnosis determination unit that detects an on / off state of the switch when the switch input determination unit stops the drive signal, and a switch diagnosis determination unit that detects an abnormality in at least the switch diagnosis determination unit. A failure determination unit that certifies a failure state, wherein the switch diagnosis determination unit detects a voltage level equivalent to the ON state of the switch when the switch input determination unit stops outputting a drive signal. A function of outputting information about an on-state switch to the failure determination unit when the failure has occurred. The vehicle-mounted switch has a function of recognizing that the switch has a failure when receiving information about the switch having the same voltage level as the ON state from the switch diagnosis determination unit. Failure diagnosis device. 2. The on-vehicle switch failure diagnosis device according to claim 1, wherein the plurality of switches are provided, and the switches are connected in a matrix by a plurality of column lines and a plurality of row lines. Having a function of outputting the drive signal to the plurality of switches through one line group of the column line and the row line, wherein the switch diagnosis determination unit includes the other of the column line and the row line Has a function of detecting the voltage level of the line group of the other, and outputting information of a plurality of switches connected to the line having the same voltage level as the ON state in the other line group to the failure determination unit. A determining unit that, when information of the plurality of switches is obtained from the switch diagnosis determining unit, recognizes all of the plurality of switches as a failure state; Automotive switch failure diagnosis apparatus characterized by having. 3. The on-vehicle switch failure diagnosis apparatus according to claim 1, wherein the failure determination unit includes a failure state switch and a failure occurrence time when the failure determination unit recognizes the failure state switch. An in-vehicle switch failure diagnosis device, further comprising a diagnosis recording unit that records abnormality information. 4. The on-vehicle switch failure diagnosis device according to claim 1, wherein when the failure determination unit recognizes a switch in a failure state, the failure determination unit replaces the switch in the failure state. And a switch function switching unit for switching so as to substitute for another switch in a normal state. 5. The on-vehicle switch failure diagnosis device according to claim 1, wherein when the failure determination unit recognizes a switch in a failure state, the failure determination unit responds to the switch in the failure state. The vehicle-mounted switch failure diagnostic device further includes a multiplex communication unit that notifies the load-side unit provided with the abnormality of an abnormality.