CAN COMMUNICATION SYSTEM Certification ECU Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Certification ECU Communication Stop Mode

  • "Entry & Start/Wireless Tuner" is not displayed on the "Communication Bus Check" screen of the intelligent tester.

  • Applies to Certification ECU Communication Stop Mode in DTC Combination Table.

  • Certification ECU branch line or connector

  • Power source circuit of Certification ECU

  • Certification ECU (Smart key ECU assembly)

WIRING DIAGRAM

B001LQWE08

CAUTION / NOTICE / HINT

Note


  • Turn the power switch off before measuring the resistances between CAN main bus lines and between CAN branch lines.

  • Turn the power switch off before inspecting CAN bus lines for a ground short.

  • After the power switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.

  • Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power switch, any other switches or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.

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 OPEN IN CAN BUS LINES (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) BRANCH LINE)


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

    2. B001KIEE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Certification ECU)

      Disconnect the H1 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
      H1-9 (CANH) - H1-10 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω

    NG

    REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))

    OK

  2. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)


    1. B001N25E02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Certification ECU)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H1-15 (E) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω

    2. Connect 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 Condition Specified Condition
      H1-1 (+B) - Body ground Power switch off 11 to 14 V
      H1-16 (IG) - Body ground Power switch on (IG) 11 to 14 V

    OK

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)