CAN COMMUNICATION SYSTEM Main Body ECU Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Main Body ECU Communication Stop Mode

Either condition is met:


  • "Main Body" is not displayed on the "CAN Bus Check" screen of the GTS Click here

  • Communication system DTCs (DTCs that start with U) that are output correspond to "Main Body ECU Communication Stop Mode" in "DTC Combination Table" Click here


  • Main body ECU (network gateway ECU) branch line or connector

  • Power source circuit of main body ECU (network gateway ECU)

  • Main body ECU (network gateway ECU) ground circuit

  • Main body ECU (network gateway ECU)

WIRING DIAGRAM

A004K8TE06
A004K8TE07

CAUTION / NOTICE / HINT

Note


  • Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key, switches or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.

  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work Click here.

  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output Click here.

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

  • DTC check procedure: Turn the ignition switch to ON and wait at least 15 seconds.

  • After the repair, perform CAN Bus Check and check that all the ECUs and sensors connected to the CAN communication system are displayed Click here.

Tech Tips


  • Operating the ignition switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.

  • Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE


  1. CHECK FOR OPEN IN CAN BUS LINES (MAIN BODY ECU (NETWORK GATEWAY ECU) BRANCH LINE)


    1. Disconnect the cable from the negative (-) battery terminal.

    2. A004I5VE03
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Main Body ECU (Network Gateway ECU))

      Disconnect the D5 main body ECU (network gateway ECU) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D5-14 (CANH) - D5-13 (CANL) Cable disconnected from negative (-) battery terminal 57 to 63 Ω

    NG

    REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (MAIN BODY ECU (NETWORK GATEWAY ECU))

    OK

  2. CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the main body ECU (network gateway ECU) Click here.

    2. Remove the instrument panel junction block assembly Click here.

      A004H3TE01
      Text in Illustration
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3E-1 - MB-8 (IG) Battery voltage is applied to terminals 3A-15 and 3A-12 Below 1 Ω
      MB-1 (BECU) - 3A-27 Always Below 1 Ω
      MB-11 (GND) - 3B-18 Always Below 1 Ω
      MB-32 (BMPX) - 3C-19 Always Below 1 Ω

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)


    1. Install the instrument panel junction block assembly.

      A004IMWE03
      Text in Illustration
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 *b

      Front view of wire harness connector

      (to Instrument Panel Junction Block Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D6-1 (GND) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω
      MB-11 (GND) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω

    3. Connect the cable to the negative (-) battery terminal.

      A004KRQE03
      Text in Illustration
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      MB-1 (BECU) - Body ground Ignition switch off 11 to 14 V
      MB-8 (IG) - Body ground Ignition switch ON 11 to 14 V
      MB-32 (BMPX) - Body ground Ignition switch off 11 to 14 V

    OK

    REPLACE MAIN BODY ECU (NETWORK GATEWAY ECU) Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)