LEMON Manuals: Even more car manuals for everyone
Home >> Toyota >> 2021 >> Mirai XLE >> Repair and Diagnosis >> Accessories & Equipment >> Communication Devices >> Can Communication System - Diagnostic Codes (3 Of 3) & Circuit Tests (1 Of 8) >> Can Communication System >> FC Control ECU Communication Stop Mode [12/2022 - 12/2023] >> Procedure

FC Control ECU Communication Stop Mode [12/2022 - 12/2023]: Procedure

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (FC CONTROL ECU MAIN WIRE) 
    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the B1 FC control ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B1-65 (CA1H) - B1-64 (CA1L) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

      Result

      Proceed to 
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT) 
    1. Disconnect the A48 FC control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A48-53 (EC) - Body ground Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω
      A48-21 (E03) - Body ground Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω
      B1-104 (E1) - Body ground Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω
      B1-105 (E2) - Body ground Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω
    3. Reconnect the cable to the negative (-) auxiliary battery terminal.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A48-2 (+BP3) - Body ground Ignition switch ON 11 to 14 V
      B1-43 (+B1) - Body ground Ignition switch ON 11 to 14 V
      B1-83 (+B2) - Body ground Ignition switch ON 11 to 14 V

      Result

      Proceed to 
      OK
      NG

    Result: 

    OK 

    REPLACE FC CONTROL ECU. Refer to  REMOVAL [12/2022 - 12/2023] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR