Trouble Diagnosis Flow Chart

DESCRIPTION

DETAIL OF TROUBLE DIAGNOSIS FLOW CHART

1.INTERVIEW WITH CUSTOMER

Interview with the customer is important to detect the root cause of CAN communication system errors and to understand vehicle condition and symptoms for proper trouble diagnosis.

Points in interview

What: Parts name, system name
When: Date, Frequency
Where: Road condition, Place
In what condition: Driving condition/environment
Result: Symptom

Notes for checking error symptoms:

Check normal units as well as error symptoms.
- Example: Circuit between ECM and the combination meter is judged normal if the customer indicates tachometer functions normally.
When a CAN communication system error is present, multiple control units may malfunction or go into fail-safe mode.
Indication of the combination meter is important to detect the root cause because it is the most obvious to the customer, and it performs CAN communication with many units.

2.INSPECTION OF VEHICLE CONDITION

Check whether the symptom is reproduced or not.

note	Do not turn the electric motor switch OFF or disconnect the 12V battery cable while reproducing the error. The error may temporarily correct itself, making it difficult to determine the root cause.

3.CHECK OF CAN SYSTEM TYPE (HOW TO USE CAN SYSTEM TYPE SPECIFICATION CHART)

Determine CAN system type based on vehicle equipment.

note	This chart is used if M.U.T.-III SE does not automatically recognize CAN system type. There are two styles for CAN system type specification charts. Depending on the number of available system types, either style A or style B may be used.

CAN System Type Specification Chart (Style A)
note CAN system type is easily checked with the vehicle equipment identification information shown in the chart.

CAN System Type Specification Chart (Style B)
note CAN system type is easily checked with the vehicle equipment identification information shown in the chart.

4.CREATE INTERVIEW SHEET

Fill out the symptom described by the customer, vehicle condition, and CAN system type on the interview sheet.

note	Interview Sheet (Example)

5.DETECT THE ROOT CAUSE

CAN diagnosis function of M.U.T.-III SE detects a root cause. Refer to EXPLANATION ABOUT THE SCAN TOOL (M.U.T.-III SE) CAN BUS DIAGNOSTICS EXPLANATION ABOUT THE SCAN TOOL (M.U.T.-III SE) CAN BUS DIAGNOSTICS

6.REPAIR OR REPLACE MALFUNCTIONING PART

Repair or replace malfunctioning parts identified by CAN diagnosis function of M.U.T.-III SE.