ECU Diagnostics via Sequential State Switching

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing on-board equipment diagnostics devices cannot accurately identify which ECU among multiple ECUs connected to a single power line is in an abnormal condition.

Innovation Solution

An on-board equipment diagnostics device that includes a current measurement section and a processor, which sends state switching signals to ECUs to switch them between wake/sleep or idle/non-idle states, measuring current values to determine if an ECU is in an abnormal condition based on predetermined thresholds.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If multiple ECUs are connected to a single power line for power saving, then power consumption is reduced, but the ability to identify which ECU is in abnormal condition deteriorates

Engineering Contradiction:

Improvepower consumptionVSAvoidabnormal condition identification accuracy

Core Design Contradiction:

Use of energy by moving objectVSMeasurement precision

Solution Approach 1:

The patent segments the power supply control by introducing individual sleep control lines to each ECU. This allows the control device to independently control the sleep state of each ECU connected to the same power line. By segmenting the control mechanism rather than the power line itself, the system maintains the power-saving benefit of shared power lines while restoring the ability to individually manage and diagnose each ECU's state through dedicated control and measurement channels.

Inventive Principle:

Principle #1Segmentation

2Device complexity

If dark current magnitude is used to determine ECU state, then power consumption monitoring is simplified, but the ability to identify specific abnormal ECUs deteriorates

Engineering Contradiction:

Improvemonitoring system complexityVSAvoidabnormal ECU identification information

Core Design Contradiction:

Device complexityVSLoss of information

Solution Approach 1:

The patent segments the measurement function by providing individual current measurement lines to each ECU. This segmentation of measurement channels allows the system to maintain simple dark current-based monitoring for each ECU individually while preventing information loss about which specific ECU is abnormal. The control device can now correlate sleep control line signals with corresponding current measurement line readings to identify the specific ECU causing abnormal current draw.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces sleep control lines and current measurement lines as intermediary channels between the control device and ECUs. These intermediary lines carry specific signals (sleep control signals and current measurements) that enable the control device to indirectly monitor and identify ECU states without requiring direct complex communication with each ECU, thus maintaining system simplicity while improving diagnostic capability.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS11642968B2On-board equipment diagnostics device, vehicle equipped with on-board equipment diagnostics device, on-board equipment diagnostics method, and non-transitory recording medium

Publication Date: 2023.05.09 TOYOTA JIDOSHA KK

AI summary

At least one power line is connected to a battery mounted at a vehicle. Plural ECUs are each connected to the at least one power line. A processor switches one ECU at a time of the plural ECUs from a second state to a first state by sending state switching signals to the plural ECUs. A power line to which plural ECUs are connected is a target power line. On the basis of current values of the target power line measured by a current measurement section when these plural ECUs are switched to the first state one at a time, the processor determines whether or not each ECU is in an abnormal condition.