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4WD Control Switch Circuit [12/2021 - ]: Procedure

  1. CONFIRM PROBLEM SYMPTOM 
    1. Confirm the problem symptoms.

      Result

      Result Proceed to
      The 4LO indicator light remains off after operating the transfer position switch (integration control and panel assembly) to L4 A
      The 4LO indicator light remains on after operating the transfer position switch (integration control and panel assembly) to H4 B

    Result: 

    B 

    See step  9

    Result: 

    A 

    See step  2

  2. CHECK 4LO INDICATOR LIGHT 

    HINT: 

    Perform the following procedure with the vehicle stopped.

    1. Turn the ignition switch to ON.
    2. Move the shift lever to N.
    3. Turn the transfer position switch (integration control and panel assembly) to L4.
    4. Check the 4LO indicator light.

      Result

      Result Proceed to
      The 4LO indicator light remains off A
      The 4LO indicator light is blinking or illuminated B

      Blinking: Blinks at 0.5 second intervals (0.5 seconds on and 0.5 seconds off)

    5. Turn the ignition switch off.

    Result: 

    B 

    END 

    Result: 

    A 

    See step  3

  3. CHECK CAN COMMUNICATION LINE 
    1. Select "Bus Check" from the System Selection Menu screen, and follow the prompts on the screen to inspect the CAN bus.

      CAN Bus Check 

      OK

      "Bus Check" indicates no malfunctions in CAN communication.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2021 - ] 

    Result: 

    OK 

    See step  4

  4. READ VALUE USING GTS (H-L SHIFT SWITCH) 
    1. Turn the ignition switch to ON.
    2. According to the display on the GTS, read the Data List.

      Powertrain > Four Wheel Drive > Data List 

      Tester Display
      H-L Shift Switch

      Powertrain > Four Wheel Drive > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      H-L Shift Switch Transfer position switch (integration control and panel assembly) status OFF or ON OFF: H4
      ON: L4      		 -

      OK

      Display changes according to transfer position switch (integration control and panel assembly) operation.

    3. Turn the ignition switch off.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  6

    Result: 

    OK 

    See step  5

  5. INSPECT COMBINATION METER ASSEMBLY (4LO INDICATOR) 
    1. Using the GTS, perform the Active Test "4LO Indicator" of the combination meter assembly.

      Body Electrical > Combination Meter > Active Test 

      Tester Display
      4LO Indicator

      OK

      The 4LO indicator light turns on or off in accordance with the GTS.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE 4 WHEEL DRIVE CONTROL ECU. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    NG 

    GO TO METER / GAUGE SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2021 - ] 

  6. CHECK HARNESS AND CONNECTOR (4 WHEEL DRIVE CONTROL ECU - TRANSFER POSITION SWITCH (INTEGRATION CONTROL AND PANEL ASSEMBLY)) 
    1. Disconnect the I201 transfer position switch (integration control and panel assembly) connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      I201-9 (2WD) - Body ground Ignition switch ON 10 to 16 V

      Result

      Proceed to
      OK
      NG
    3. Connect the I201 transfer position switch (integration control and panel assembly) connector.

    Result: 

    NG 

    See step  8

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (TRANSFER POSITION SWITCH (INTEGRATION CONTROL AND PANEL ASSEMBLY) - BODY GROUND) 
    1. Disconnect the I201 transfer position switch (integration control and panel assembly) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I201-6 (E) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG
    3. Connect the I201 transfer position switch (integration control and panel assembly) connector.

    Result: 

    OK 

    REPLACE INTEGRATION CONTROL AND PANEL ASSEMBLY. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  8. CHECK HARNESS AND CONNECTOR (4 WHEEL DRIVE CONTROL ECU - TRANSFER POSITION SWITCH (INTEGRATION CONTROL AND PANEL ASSEMBLY)) 
    1. Disconnect the B9 4 wheel drive control ECU connector.
    2. Disconnect the I201 transfer position switch (integration control and panel assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B9-11 (LO) - I201-9 (2WD) Always Below 1 Ω
      B9-11 (LO) or I201-9 (2WD) - Body ground Always 10 kΩ or higher
      I201-6 (E) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG
    4. Connect the I201 transfer position switch (integration control and panel assembly) connector.
    5. Connect the B9 4 wheel drive control ECU connector.

    Result: 

    OK 

    REPLACE 4 WHEEL DRIVE CONTROL ECU. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  9. CHECK 4LO INDICATOR LIGHT 

    HINT: 

    Perform the following procedure with the vehicle stopped.

    1. Turn the ignition switch to ON.
    2. Move the shift lever to N.
    3. Turn the transfer position switch (integration control and panel assembly) to L4.
    4. Check the 4LO indicator light.

      Result

      Result Proceed to
      The 4LO indicator light remains illuminated A
      The 4LO indicator light is blinking or illuminated B

      Blinking: Blinks at 0.5 second intervals (0.5 seconds on and 0.5 seconds off)

    5. Turn the ignition switch off.

    Result: 

    B 

    END 

    Result: 

    A 

    See step  10

  10. CHECK CAN COMMUNICATION LINE 
    1. Select "Bus Check" from the System Selection Menu screen, and follow the prompts on the screen to inspect the CAN bus.

      CAN Bus Check 

      OK

      "Bus Check" indicates no malfunctions in CAN communication.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    CHECK CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2021 - ] 

    Result: 

    OK 

    See step  11

  11. READ VALUE USING GTS (L4 INDICATOR REQUEST) 
    1. Turn the ignition switch to ON.
    2. According to the display on the GTS, read the Data List.

      Powertrain > Four Wheel Drive > Data List 

      Tester Display
      L4 Indicator Request

      Powertrain > Four Wheel Drive > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      L4 Indicator Request 4LO indicator light request OFF, ON, Blink1, Blink2 or Blink3 OFF: Indicator light turns off
      ON: Indicator light illuminates
      Blink1: Indicator light blinks
      Blink2: Indicator light blinks 3 times
      Blink3: Indicator light rapidly blinks
      • Blinking: 0.5 second intervals (0.5 seconds on and 0.5 seconds off)
      • Rapidly blinking: 0.25 second intervals (0.25 seconds on and 0.25 seconds off)
      1. Operate the transfer position switch (integration control and panel assembly) several times between H4 and L4, and then check the GTS display condition of the 4LO indicator light.

        Result

        Result Proceed to
        Data List continues to display ON even when transfer position switch (integration control and panel assembly) is operated A
        Data List display changes according to transfer position switch (integration control and panel assembly) operation B

    Result: 

    A 

    REPLACE 4 WHEEL DRIVE CONTROL ECU. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    B 

    GO TO METER / GAUGE SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2021 - ] 

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