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DTC U1002 (CAN No. 2 BUS), U0114: Lost Communication with Gateway Module (Network Gateway ECU); Lost Communication with 4WD Control ECU: Procedure

  1. CHECK CAN NO. 2 BUS WIRE 
    1. Turn the ignition switch off.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 1: Identifying Network Gateway ECU And E15 Connector Terminals
      GTY243762Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Result Proceed to
      E53-13 (CA2H) - E53-12 (CA2L) Ignition switch off 54 to 69 Ω Below 53 Ω: Short in line
      70 Ω or higher: Open in CAN main bus line
      E53-13 (CA2H) - E15-16 (BAT) Cable is disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ: +B short
      E53-12 (CA2L) - E15-16 (BAT) Cable is disconnected from negative (-) battery terminal 6 kΩ or higher Below 6 kΩ: +B short
      E53-13 (CA2H) - E15-4 (CG) Ignition switch off 200 Ω or higher Below 200 Ω: Ground short
      E53-12 (CA2L) - E15-4 (CG) Ignition switch off 200 Ω or higher Below 200 Ω: Ground short

      Result

      Result Proceed to
      OK A
      Open in CAN main bus line B
      • Short in line
      • +B short
      • Ground short
      		 C

    C → See step   13 

    B → See step   10 

    A: Go to next step 

  2. CHECK OPEN IN CAN BUS WIRE (4WD CONTROL ECU) 
    1. Turn the ignition switch off.
    2. Disconnect the 4WD control ECU connector.
    3. Measure the resistance according to the value(s) in the table below.
      Fig 2: Identifying 4WD Control ECU Connector Terminals
      GTY226195Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      E17-14 (CANH) - E17-16 (CANL) Ignition switch off 54 to 69 Ω

    NG → REPAIR OR REPLACE CAN NO. 2 BUS BRANCH WIRE OR CONNECTOR (4WD CONTROL ECU BRANCH WIRE) 

    OK: Go to next step 

  3. CHECK WIRE HARNESS (4WD CONTROL ECU - BATTERY AND BODY GROUND) 
    1. Disconnect the 4WD control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 3: Identifying 4WD Control ECU Connector Terminals
      GTY244890Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      E17-23 (GND) - Body ground Ignition switch off Below 1 Ω
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      E17-11 (IG1) - Body ground Ignition switch on 10 to 14 V

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (4WD CONTROL ECU POWER SOURCE CIRCUIT) 

    OK: Go to next step 

  4. CONNECT 
    1. Reconnect the 4WD control ECU connector.

    NEXT: Go to next step 

  5. CLEAR DTC 
    1. Clear the DTC.

    NEXT: Go to next step 

  6. RECONFIRM DTC OUTPUT 
    1. Check the DTC.

      Result

      Result Proceed to
      DTC U0114 and U1002 are not output A
      DTC U0114 and U1002 are output B

    B → See step   8 

    A → See step   7 

  7. CHECK CONNECTOR CONNECTION CONDITION. Refer to  ELECTRONIC CIRCUIT INSPECTION PROCEDURE 
  8. REPLACE NETWORK GATEWAY ECU 

    Refer to REMOVAL

    1. Replace the network gateway ECU.

    NEXT: Go to next step 

  9. RECONFIRM DTC OUTPUT 
    1. Check the DTC.

      Result

      Result Proceed to
      DTC U0114 and U1002 are not output A
      DTC U0114 and U1002 are output B

    B → See step   17 

    A → END 

  10. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (NETWORK GATEWAY ECU - CAN NO. 3 JUNCTION CONNECTOR) 
    1. Disconnect the network gateway ECU connector.
    2. Measure the resistance of the wire harness side connectors.
      Fig 4: Identifying Network Gateway ECU Connector Terminals
      GTY243741Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      E53-13 (CA2H) - E53-12 (CA2L) Ignition switch off 108 to 132 Ω

    NG → See step   11 

    OK → See step   8 

  11. CONNECT 
    1. Reconnect the network gateway ECU connector.

    NEXT: Go to next step 

  12. CHECK FOR OPEN IN CAN NO. 2 BUS MAIN WIRE (CAN NO. 3 JUNCTION CONNECTOR - NETWORK GATEWAY ECU) 
    1. Disconnect the CAN No. 3 junction connector (E68).
    2. Measure the resistance according to the value(s) in the table below.
      Fig 5: Identifying CAN No. 3 Junction Connector (E68) Connector Terminals
      GTY243747Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      E68-1 (CANH) - E68-2 (CANL) Ignition switch off 108 to 132 Ω

    NG → See step   16 

    OK → REPAIR OR REPLACE INSTRUMENT PANEL WIRE (CAN NO. 3 JUNCTION CONNECTOR) 

  13. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE 
    1. Disconnect the network gateway ECU connector.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 6: Identifying Network Gateway ECU And DLC3 Connector Terminals
      GTY210860Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Result
      E53-13 (CA2H) - E53-12 (CA2L) Ignition switch off 108 to 132 Ω
      E53-13 (CA2H) - E15-16 (BAT) Cable is disconnected from negative (-) battery terminal 6 kΩ or higher
      E53-12 (CA2L) - E15-16 (BAT) Cable is disconnected from negative (-) battery terminal 6 kΩ or higher
      E53-13 (CA2H) - E15-4 (CG) Ignition switch off 200 Ω or higher
      E53-12 (CA2L) - E15-4 (CG) Ignition switch off 200 Ω or higher

    NG → See step   14 

    OK → See step   8 

  14. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (4WD CONTROL ECU BRANCH WIRE) 
    1. Disconnect the CAN No. 3 junction connector (E66).
      Fig 7: Identifying CAN No. 3 Junction Connector (E66) Connector Terminals
      GTY229511Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.
      Fig 8: Identifying Network Gateway ECU And DLC3 Connector Terminals
      GTY244363Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      E53-13 (CA2H) - E53-12 (CA2L) Ignition switch off 108 to 132 Ω
      E53-13 (CA2H) - E15-16 (BAT) Cable is disconnected from negative (-) battery terminal 6 kΩ or higher
      E53-12 (CA2L) - E15-16 (BAT) Cable is disconnected from negative (-) battery terminal 6 kΩ or higher
      E53-13 (CA2H) - E15-4 (CG) Ignition switch off 200 Ω or higher
      E53-12 (CA2L) - E15-4 (CG) Ignition switch off 200 Ω or higher

    NG → See step   16 

    OK: Go to next step 

  15. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (4WD CONTROL ECU BRANCH WIRE) 
    1. Disconnect the 4WD control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 9: Identifying 4WD Control ECU And DLC3 Connector Terminals
      GTY244886Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      E17-14 (CANH) - E17-16 (CANL) Ignition switch off 1 MΩ or higher
      E17-14 (CANH) - E15-16 (BAT) Cable is disconnected from negative (-) battery terminal 6 kΩ or higher
      E17-16 (CANL) - E15-16 (BAT) Cable is disconnected from negative (-) battery terminal 6 kΩ or higher
      E17-14 (CANH) - E17-23 (GND) Ignition switch off 200 Ω or higher
      E17-16 (CANL) - E17-23 (GND) Ignition switch off 200 Ω or higher

    NG → REPAIR OR REPLACE CAN NO. 2 BUS BRANCH WIRE OR CONNECTOR (4WD CONTROL ECU BRANCH WIRE) 

    OK → See step   17 

  16. CHECK FOR SHORT IN CAN NO. 2 BUS WIRE (CAN NO. 3 JUNCTION CONNECTOR - NETWORK GATEWAY MAIN WIRE) 
    1. Disconnect the CAN No. 3 junction connector (E68).
      Fig 10: Identifying CAN No. 3 Junction Connector (E68) Connector Terminals
      GTY243747Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.
      Fig 11: Identifying Network Gateway ECU And DLC3 Connector Terminals
      GTY244363Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      E53-13 (CA2H) - E53-12 (CA2L) Ignition switch off 1 MΩ or higher
      E53-13 (CA2H) - E15-16 (BAT) Cable is disconnected from negative (-) battery terminal 6 kΩ or higher
      E53-12 (CA2L) - E15-16 (BAT) Cable is disconnected from negative (-) battery terminal 6 kΩ or higher
      E53-13 (CA2H) - E15-4 (CG) Ignition switch off 200 Ω or higher
      E53-12 (CA2L) - E15-4 (CG) Ignition switch off 200 Ω or higher

    NG → REPAIR OR REPLACE CAN NO. 2 BUS MAIN WIRE OR CONNECTOR (NETWORK GATEWAY ECU - CAN NO. 3 JUNCTION CONNECTOR) 

    OK → REPAIR OR REPLACE INSTRUMENT PANEL WIRE (CAN NO. 3 JUNCTION CONNECTOR) 

  17. REPLACE 4WD ECU ASSEMBLY. Refer to  REMOVAL 
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