Open in Bus 3 Main Bus Line [11/2015 - ]: Procedure

2018 Toyota Prius Two EcoSECTION Procedure
  1. CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 4 CAN JUNCTION CONNECTOR) 
    1. Disconnect the cable from the negative (-) auxiliary battery terminal.
    2. Disconnect the F72 No. 4 CAN junction connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      (F72)

      (F72)

      Tester Connection Condition Specified Condition Connected to
      F72-3 (CANH) - F72-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Central gateway ECU (network gateway ECU)
      F72-4 (CANH) - F72-15 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Central gateway ECU (network gateway ECU)

      Result

      Result
      OK
      NG

    Result: 

    OK 

    REPLACE NO. 4 CAN JUNCTION CONNECTOR 

    Result: 

    NG 

    See step  2

  2. CHECK FOR OPEN IN CAN MAIN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 4 CAN JUNCTION CONNECTOR) 
    1. Reconnect the F72 No. 4 CAN junction connector.
    2. Disconnect the F59 central gateway ECU (network gateway ECU) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      (F59)

      (F59)

      Tester Connection Condition Specified Condition
      F59-6 (CA3H) - F59-19 (CAYH) Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω
      F59-21 (CA3L) - F59-20 (CAYL) Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω

      Result

      Result
      OK
      NG

    Result: 

    OK 

    REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU). Refer to  REMOVAL [11/2015 - 08/2019]  , or refer to  REMOVAL [08/2019 - 07/2020]  , or refer to  REMOVAL [07/2020 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 4 CAN JUNCTION CONNECTOR) 

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.