CAN COMMUNICATION SYSTEM(for RHD), Diagnostic DTC:U0001

DTC Code DTC Name
U0001 High Speed CAN Communication Bus

DESCRIPTION

DTC No. Detection Item DTC Detection Condition Trouble Area
U0001 High Speed CAN Communication Bus

The diagnosis data record ECU is unable to receive data from all of the following ECUs for 3.1 seconds or more continuously.


  • FC converter assembly

  • Hydrogen fuel control ECU assembly

  • FC control ECU

  • EV control ECU

  • Diagnosis data record ECU branch line or connector

  • Power source circuit of diagnosis data record ECU

  • Diagnosis data record ECU ground circuit

  • Diagnosis data record ECU

WIRING DIAGRAM

A01MFJXE02

CAUTION / NOTICE / HINT

Note


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

  • After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary 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.

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

  • DTC check procedure: Turn the power switch on (IG) and wait at least 2 minutes.

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

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  • Inspect the fuses for circuits related to this system before performing the following procedure.

Tech Tips


  • Operating the power 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 DTC (FC CONTROL SYSTEM)


    1. Check if FC control system DTCs are output.

      Click here


      Powertrain > FC > Trouble Codes
      OK
      FC control system DTCs are not output.
      Result
      Result
      OK
      NG

    NG

    GO TO FC CONTROL SYSTEM Click here

    OK

  2. CHECK FOR DTC (FC BOOST CONTROL SYSTEM)


    1. Check if FC boost control system DTCs are output.

      Click here


      Powertrain > FCDC > Trouble Codes
      OK
      FC boost control system DTCs are not output.
      Result
      Result
      OK
      NG

    NG

    GO TO FC BOOST CONTROL SYSTEM Click here

    OK

  3. CHECK FOR DTC (HYBRID CONTROL SYSTEM)


    1. Check if hybrid control system DTCs are output.

      Click here


      Powertrain > EV > Trouble Codes
      OK
      Hybrid control system DTCs are not output.
      Result
      Result
      OK
      NG

    NG

    GO TO HYBRID CONTROL SYSTEM Click here

    OK

  4. CHECK FOR OPEN IN CAN BUS LINES (DIAGNOSIS DATA RECORD ECU BRANCH LINE)


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

    2. Disconnect the diagnosis data record ECU connector.

    3. A01MGO0C03
      *a

      Front view of wire harness connector

      (to Diagnosis Data Record ECU)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G38-13 (CANH) - G38-12 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω
      Result
      Result
      OK
      NG

    NG

    REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (DIAGNOSIS DATA RECORD ECU)

    OK

  5. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)


    1. A01MGO0C04
      *a

      Front view of wire harness connector

      (to Diagnosis Data Record ECU)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G38-4 (GND) - Body ground Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω

    2. Reconnect the cable to the negative (-) auxiliary battery terminal.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      G38-10 (IG1) - Body ground Power switch on (IG) 11 to 14 V
      G38-2 (BATT) - Body ground Power switch off 11 to 14 V
      Result
      Result
      OK
      NG

    OK

    REPLACE DIAGNOSIS DATA RECORD ECU Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)