US-12625182-B2 - Malfunction detection method and electronic control device capable of detecting malfunction

US12625182B2US 12625182 B2US12625182 B2US 12625182B2US-12625182-B2

Abstract

A malfunction detection method detects a malfunction in an electronic control device. The electronic control device includes a normal power supply terminal connected to a normal power supply mounted on a vehicle, a starting power supply terminal connected to a starting power supply, a controller activated by supply of a normal voltage, and a wake-up circuit having a wake-up switch to open and close a power supply path from the normal power supply terminal to the controller. The wake-up circuit turns on the wake-up switch when a starting voltage input to the starting power supply terminal is equal to or greater than an ON threshold. The malfunction detection method includes determining by the controller that the wake-up switch has an ON sticking malfunction when the normal voltage is equal to or greater than a threshold and the starting voltage is less than the ON threshold.

Inventors

Tsuyoshi TASHIMA
Daisuke Kobayashi
Masaya Taki
Ryo KANO
Hisashi Kameya

Assignees

DENSO CORPORATION

Dates

Publication Date: 20260512
Application Date: 20231129
Priority Date: 20210601

Claims (13)

1 . A malfunction detection method for detecting a malfunction in an electronic control device including a normal power supply terminal connected to a normal power supply mounted on a vehicle, a starting power supply terminal connected to a starting power supply via a starting switch that is turned on when the vehicle is started, a controller which is activated by a supply of a normal voltage that is input from the normal power supply via the normal power supply terminal, and a wake-up circuit having a wake-up switch configured to open and close a power supply path from the normal power supply terminal to the controller, the wake-up circuit being configured to turn on the wake-up switch to open the power supply path when a starting voltage that is input to the starting power supply terminal is equal to or greater than an ON threshold, the ON threshold indicating a state of the starting voltage between the starting power supply and the controller, the malfunction detection method comprising determining by the controller that the wake-up switch has an ON sticking malfunction when the normal voltage is equal to or greater than a determination threshold and the starting voltage is less than the ON threshold, the determination threshold indicating a state of the normal voltage between the normal power supply and the controller.
2 . The malfunction detection method according to claim 1 , wherein the determining by the controller is performed when the controller is activated by switching of a state of connection between the normal power supply and the normal power supply terminal is switched from a disconnected state to a connected state.
3 . The malfunction detection method according to claim 1 , wherein the wake-up switch being provided inside the electronic control device with respect to the starting power supply terminal.
4 . The malfunction detection method according to claim 1 , wherein the wake-up circuit is provided inside an IC.
5 . The malfunction detection method according to claim 1 , wherein the wake-up circuit includes the wake-up switch and a determination circuit configured to determine whether the starting voltage is equal to or greater than the ON threshold when the starting switch is turned on, and the wake-up switch and the determination circuit are provided inside an IC.
6 . A malfunction detection method for detecting a malfunction in an electronic control device including a normal power supply terminal connected to a normal power supply mounted on a vehicle, a starting power supply terminal connected to a starting power supply via a starting switch that is turned on when the vehicle is started, a controller which is activated by a supply of a normal voltage that is input from the normal power supply via the normal power supply terminal, and a wake-up circuit having a wake-up switch configured to open and close a power supply path from the normal power supply terminal to the controller, the wake-up circuit being configured to turn on the wake-up switch to open the power supply path when a starting voltage that is input to the starting power supply terminal is equal to or greater than an ON threshold, the ON threshold indicating a state of the starting voltage between the starting power supply and the controller, the malfunction detection method comprising determining by the controller that the wake-up switch has an ON sticking malfunction when the controller is operating and the starting voltage is less than the ON threshold.
7 . The malfunction detection method according to claim 6 , wherein the wake-up switch being provided inside the electronic control device with respect to the starting power supply terminal.
8 . The malfunction detection method according to claim 6 , wherein the wake-up circuit is provided inside an IC.
9 . The malfunction detection method according to claim 6 , wherein the wake-up circuit includes the wake-up switch and a determination circuit configured to determine whether the starting voltage is equal to or greater than the ON threshold when the starting switch is turned on, and the wake-up switch and the determination circuit are provided inside an IC.
10 . An electronic control device capable of detecting a malfunction, the electronic control device comprising: a normal power supply terminal connected to a normal power supply mounted on a vehicle; a starting power supply terminal connected to a starting power supply via a starting switch that is turned on when the vehicle is started; a controller which is activated by a supply of a normal voltage that is input from the normal power supply via the normal power supply terminal; and a wake-up circuit having a wake-up switch configured to open and close a power supply path from the normal power supply terminal to the controller, wherein the wake-up circuit is configured to turn on the wake-up switch to open the power supply path when a starting voltage that is input to the starting power supply terminal is equal to or greater than an ON threshold, the ON threshold indicating a state of the starting voltage between the starting power supply and the controller, the controller is configured to determine that the wake-up switch has an ON sticking malfunction when the normal voltage is equal to or greater than a determination threshold and the starting voltage is less than the ON threshold or when the controller is operating and the starting voltage is less than the ON threshold, the determination threshold indicating a state of the normal voltage between the normal power supply and the controller.
11 . The electronic control device according to claim 10 , wherein the wake-up switch being provided inside the electronic control device with respect to the starting power supply terminal.
12 . The electronic control device according to claim 10 , wherein the wake-up circuit is provided inside an IC.
13 . The electronic control device according to claim 10 , wherein the wake-up circuit includes the wake-up switch and a determination circuit configured to determine whether the starting voltage is equal to or greater than the ON threshold when the starting switch is turned on, and the wake-up switch and the determination circuit are provided inside an IC.

Description

CROSS REFERENCE TO RELATED APPLICATIONS The present application is a continuation application of International Patent Application No. PCT/JP2022/020063 filed on May 12, 2022, which designated the U.S. and claims the benefit of priority from Japanese Patent Application No. 2021-092321 filed on Jun. 1, 2021. The entire disclosures of all of the above applications are incorporated herein by reference. TECHNICAL FIELD The present disclosure relates to a malfunction detection method and an electronic control device capable of detecting a malfunction. BACKGROUND Conventionally, techniques for detecting a sticking malfunction of a power relay provided in a power supply circuit are known. SUMMARY According to at least one embodiment, a malfunction detection method detects a malfunction in an electronic control device. The electronic control device includes a normal power supply terminal connected to a normal power supply mounted on a vehicle, a starting power supply terminal connected to a starting power supply via a starting switch that is turned on when the vehicle is started, a controller which is activated by supply of a normal voltage input from the normal power supply via the normal power supply terminal, and a wake-up circuit having a wake-up switch to open and close a power supply path from the normal power supply terminal to the controller. The wake-up circuit turns on the wake-up switch to open the power supply path when a starting voltage input to the starting power supply terminal is equal to or greater than an ON threshold. The malfunction detection method includes determining by the controller that the wake-up switch has an ON sticking malfunction when the normal voltage is equal to or greater than a threshold and the starting voltage is less than the ON threshold. BRIEF DESCRIPTION OF DRAWINGS The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features and advantages will be apparent from the description and drawings, and from the claims. The above and other objectives, features and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings. In the drawings: FIG. 1 is a diagram of a system configuration example to which a malfunction detection method of the present embodiment is applied; FIG. 2 is a timing chart illustrating an operation of electronic control unit (i.e., ECU) in a normal state; FIG. 3 is a time chart illustrating the malfunction detection method of the present embodiment; FIG. 4 is a diagram illustrating a voltage supply state after an ignition switch is turned off before the auxiliary battery is detached and after the auxiliary battery is reattached; FIG. 5 is a diagram illustrating a voltage non-supply state during detaching of the auxiliary battery; FIG. 6 is a flowchart illustrating the malfunction detection method of the present embodiment; FIG. 7 is a diagram of another system configuration example to which the malfunction detection method of the present embodiment is applied; FIG. 8 is a diagram of another system configuration example to which the malfunction detection method of the present embodiment is applied. DETAILED DESCRIPTION To begin with, examples of relevant techniques will be described. Conventionally, techniques for detecting a sticking malfunction of a power relay provided in a power supply circuit are known. For example, an abnormality diagnosis device disclosed according to a comparative example stores, in a storage unit, information indicating that a power relay has an ON sticking malfunction when a capacitor voltage does not decrease and a microcomputer is capable of operating even though a predetermined time has elapsed after an ignition switch and a power relay are turned off. After that, the microcomputer reads the malfunction information stored in the storage unit and determines that the power relay has an ON sticking malfunction when the ignition switch is turned on again. In techniques of the comparative example, after a system is temporarily stopped, that is, at the time of restart after a vehicle is parked or stopped, a malfunction is determined based on information stored in the storage unit. Therefore, in a case where the stored information is changed due to some factor while the system is stopped, the microcomputer may read out erroneous information at the time of restart and make an erroneous determination. For example, even if the power relay is actually normal, it will be incorrectly determined that the power relay has failed when the stored information is changed to malfunction information. In a case where a calculation processing device (i.e., CPU) of the microcomputer is reset as a measure at the time of malfunction determination, operations 1 to 4 of <1> resetting the CPU, <2> restarting the CPU, <3> erroneously determining a malfunction due to garbled stored information, and <4> resetting ar