CAN COMMUNICATION SYSTEM (for RHD) Certification ECU Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Certification ECU Communication Stop Mode

Either Condition is met:


  • "Certification (Smart)" is not displayed on the "Bus Check" screen Click here.

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

  • Certification ECU (smart key ECU assembly) main line or connector

  • Power source circuit of certification ECU (smart key ECU assembly)

  • Certification ECU (smart key ECU assembly) ground circuit

  • Certification ECU (smart key ECU assembly)

WIRING DIAGRAM

A01FHJ7E02

INSPECTION PROCEDURE

Note


  • 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.

  • Before measuring the resistance of the CAN bus, turn the engine 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 engine switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Click here.

  • Before replacing the certification ECU (smart key ECU assembly), refer to the entry and start system (for Entry Function) Click here.

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

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

  • DTC check procedure: Turn the engine switch on (IG) and wait at least 20 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 engine switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

  • 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 WIRE (CERTIFICATION ECU CAN MAIN WIRE)


    1. A01FG5XE01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Certification ECU [Smart Key ECU Assembly])

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

    2. Disconnect the certification ECU (smart key ECU assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      N93-14 (CANH) - N93-15 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω

    NG

    REPAIR OR REPLACE CERTIFICATION ECU CAN MAIN WIRE OR CONNECTOR (CANH, CANL)

    OK

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - BATTERY AND BODY GROUND)


    1. A01FFNEE01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Certification ECU [Smart Key ECU Assembly])

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

      Note

      When connecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. Disconnect the certification ECU (smart key ECU assembly) connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A34-2 (+B) - Body ground Always 11 to 14 V
      A34-10 (CUTB) - Body ground Always 11 to 14 V
      N93-5 (IG) - Body ground Engine switch on (IG) 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A34-11 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)