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Trouble Diagnosis Flow Chart

DESCRIPTION 

GNSDB108915Courtesy of NISSAN NORTH AMERICA, INC.

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.
    GNSDB109723Courtesy of NISSAN NORTH AMERICA, INC.

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    GO TO 2.

  2. INSPECTION OF VEHICLE CONDITION 

    Check whether the symptom is reproduced or not.

    NOTE: SYMBOL Do not turn the ignition 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.

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    GO TO 3.

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

    Determine CAN system type based on vehicle equipment.

    NOTE: SYMBOL
    • This chart is used if CONSULT 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: SYMBOL CAN system type is easily checked with the vehicle equipment identification information shown in the chart.
      GNSDB111076Courtesy of NISSAN NORTH AMERICA, INC.
    • CAN System Type Specification Chart (Style B)
      NOTE: SYMBOL CAN system type is easily checked with the vehicle equipment identification information shown in the chart.
      GNSDB111085Courtesy of NISSAN NORTH AMERICA, INC.

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    GO TO 4.

  4. CREATE INTERVIEW SHEET 

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

    NOTE: SYMBOL Interview Sheet (Example)
    GNSDB109291Courtesy of NISSAN NORTH AMERICA, INC.

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    GO TO 5.

  5. DETECT THE ROOT CAUSE 

    CAN diagnosis function of CONSULT detects a root cause.

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    GO TO 6.

  6. REPAIR OR REPLACE MALFUNCTIONING PART 

    Repair or replace malfunctioning parts identified by CAN diagnosis function of CONSULT.

    Vehicle CAN communication 1 circuit>>

    Refer to Vehicle CAN Communication 1 Circuit .

    Vehicle CAN communication 2 circuit>>

    Refer to Vehicle CAN Communication 2 Circuit .

    Drivetrain CAN communication circuit>>

    Refer to Drivetrain CAN Communication Circuit .

    ITS CAN communication 1 circuit>>

    Refer to ITS CAN Communication 1 Circuit .

    ITS CAN communication 2 circuit>>

    Refer to ITS CAN Communication 2 Circuit .

    Chassis CAN communication 1 circuit>>

    Refer to Chassis CAN Communication 1 Circuit .

    Chassis CAN communication 2 circuit>>

    Refer to Chassis CAN Communication 2 Circuit .

    ADAS CAN communication 1 circuit>>

    Refer to ADAS CAN Communication 1 Circuit .

    IT CAN communication circuit>>

    Refer to IT CAN Communication Circuit .

    Diagnostic CAN communication circuit>>

    Refer to Diagnostic CAN Communication Circuit .