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DTC U0137-87: Lost Communication With Trailer Brake Control Module Missing Message [09/2022 - ]: Procedure

  1. CHECK CAN BUS MAIN WIRE (OPEN OR SHORT IN POWERTRAIN LOCAL BUS) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the ECM connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A11-16 (CACH) - A11-15 (CACL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω
      A11-16 (CACH) or A11-15 (CACL) - Other supply terminals Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      A11-16 (CACH) or A11-15 (CACL) - Body ground Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. None

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (TRAILER BRAKE CONTROL ECU - ECM) 

    Pre-procedure1

    1. Disconnect the trailer brake control ECU connector.
    2. Disconnect the ECM connector.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I14-40 (CA2H) - A11-16 (CACH) Ignition switch off Below 1 Ω
      I14-39 (CA2L) - A11-15 (CACL) Ignition switch off Below 1 Ω
      I14-40 (CA2H) or A11-16 (CACH) - Body ground and other terminals Ignition switch off 10 kΩ or higher
      I14-39 (CA2L) or A11-15 (CACL) - Body ground and other terminals Ignition switch off 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. None

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK TERMINAL VOLTAGE OF TRAILER BRAKE CONTROL ECU (+B) 

    Refer to PROCEDURE - Step 3

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPAIR OR REPLACE ECU POWER SOURCE CIRCUIT 

    Refer to DTC C105F-62: IGR Voltage / Actuator Supply Voltage Signal Compare Failure [09/2022 - ]

    Result: 

    OK 

    See step  4

  4. CHECK TERMINAL VOLTAGE OF TRAILER BRAKE CONTROL ECU (IGR) 

    Refer to PROCEDURE - Step 2

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPAIR OR REPLACE ECU POWER SOURCE CIRCUIT 

    Refer to DTC C105F-62: IGR Voltage / Actuator Supply Voltage Signal Compare Failure [09/2022 - ]

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (TRAILER BRAKE CONTROL ECU - BODY GROUND) 

    Refer to PROCEDURE - Step 4

    Result

    Proceed to
    OK
    NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. REPLACE TRAILER BRAKE CONTROL ECU (BRAKE CONTROL WITH BRACKET RELAY) 

    HINT: 

    Refer to REMOVAL [09/2022 - ]

    Result

    Proceed to
    NEXT

    Result: 

    NEXT 

    See step  7

  7. CLEAR DTC 

    Pre-procedure1

    1. None

      Procedure1

    2. Clear the DTCs.

      Powertrain > Engine > Clear DTCs 

      Result

      Proceed to
      NEXT

      Post-procedure1

    3. Turn the ignition switch off and wait for at least 30 seconds.

    Result: 

    NEXT 

    See step  8

  8. CHECK WHETHER DTC OUTPUT RECURS (DTC U0137-87) 

    Pre-procedure1

    1. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.

      Procedure1

    2. Read the DTCs.

      Powertrain > Engine > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output A
      U0137-87 is output B

      Post-procedure1

    3. None

    Result: 

    A 

    END 

    Result: 

    B 

    REPLACE ECM 

    Refer to REMOVAL [09/2022 - ]

  9. INSPECT TRAILER BRAKE CONTROL ECU 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the trailer brake control ECU connector.

      HINT: 

      Check the other ECUs are connected.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I14-40 (CA2H) - I14-39 (CA2L) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω
      I14-40 (CA2H) or I14-39 (CA2L) - Other supply terminals Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      I14-40 (CA2H) or I14-39 (CA2L) - Body ground Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. None

    Result: 

    OK 

    REPLACE TRAILER BRAKE CONTROL ECU (BRAKE CONTROL WITH BRACKET RELAY) 

    Refer to REMOVAL [09/2022 - ]

    Result: 

    NG 

    See step  10

  10. INSPECT HYBRID VEHICLE CONTROL ECU 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the hybrid vehicle control ECU connector.

      HINT: 

      Check the other ECUs are connected.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I4-24 (CA3P) - I4-11 (CA3N) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      I4-24 (CA3P) or I4-11 (CA3N) - Other supply terminals Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      I4-24 (CA3P) or I4-11 (CA3N) - Body ground Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. None

    Result: 

    OK 

    REPLACE HYBRID VEHICLE CONTROL ECU 

    Refer to REMOVAL [09/2022 - ]

    Result: 

    NG 

    See step  11

  11. INSPECT NO. 2 SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the No. 2 skid control ECU (brake actuator assembly) connector.

      HINT: 

      Check the other ECUs are connected.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A21-16 (CA2H) - A21-17 (CA2L) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      A21-16 (CA2H) or A21-17 (CA2L) - Other supply terminals Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      A21-16 (CA2H) or A21-17 (CA2L) - Body ground Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. None

    Result: 

    OK 

    REPLACE NO. 2 SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY) 

    Refer to REMOVAL [09/2022 - ]

    Result: 

    NG 

    See step  12

  12. INSPECT NO. 1 SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) 

    Pre-procedure1

    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the No. 1 skid control ECU (brake booster with master cylinder assembly) connector.

      HINT: 

      Check the other ECUs are connected.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A20-35 (CA2H) - A20-36 (CA2L) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω
      A20-35 (CA2H) or A20-36 (CA2L) - Other supply terminals Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      A20-35 (CA2H) or A20-36 (CA2L) - Body ground Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. None

    Result: 

    OK 

    REPLACE NO. 1 SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) 

    Refer to REMOVAL [09/2022 - ]

    Result: 

    NG 

    See step  13

  13. INSPECT BATTERY VOLTAGE SENSOR 
    WARNING:

    Be sure to wear insulated gloves.

    Pre-procedure1

    1. Check that the service plug grip is not installed.
      NOTE:

      After removing the service plug grip, do not turn the ignition switch to ON (READY), unless instructed by the appropriate service information because this may cause a malfunction.

    2. Disconnect the cable from the negative (-) auxiliary battery terminal.
    3. Disconnect the battery voltage sensor connector.

      HINT: 

      Check the other ECUs are connected.

      Procedure1

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      j1-2 (CA1H) - j1-3 (CA1L) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω
      j1-2 (CA1H) or j1-3 (CA1L) - Other supply terminals Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      j1-2 (CA1H) or j1-3 (CA1L) - Body ground Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    5. None

    Result: 

    OK 

    REPLACE BATTERY VOLTAGE SENSOR 

    Refer to REMOVAL [09/2022 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWERTRAIN LOCAL BUS) 

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