CAN COMMUNICATION SYSTEM Engine Stop and Start ECU Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Engine Stop and Start ECU Communication Stop Mode

Either condition is met:


  • "Stop and Go/Start" is not displayed on "CAN Bus Check".

  • "Engine Stop and Start ECU Communication Stop Mode" in "DTC Combination Table" applies.

  • Power source or inside engine stop and start ECU

  • Engine stop and start ECU CAN branch wire or connector

  • Engine stop and start ECU CAN branch wire or connector

WIRING DIAGRAM

A01IUC1E01

INSPECTION PROCEDURE

Note

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

Tech Tips

Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

PROCEDURE


  1. PRECAUTION

    Note

    After turning the ignition 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.


    NEXT

  2. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the CAB main wire and the CAN branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note

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


    NEXT

  3. CHECK FOR OPEN IN CAN BUS WIRE (ENGINE STOP AND START ECU CAN BRANCH WIRE)


    1. A01IOU5E20

      Disconnect the engine stop and start ECU connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H121-15 (CANH) - H121-16 (CANL) Ignition switch off 54 to 69 Ω
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Engine Stop and Start ECU)

    NG

    REPAIR OR REPLACE ENGINE STOP AND START ECU CAN BRANCH WIRE OR CONNECTOR (CANH, CANL)

    OK

  4. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - BATTERY AND BODY GROUND)


    1. A01ITZ4E01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Engine Stop and Start ECU)

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

      Note

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

    2. Disconnect the engine stop and start ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A73-8 (GND) - Body ground Always Below 1 Ω

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A73-7 (BIN) - Body ground Always 11 to 14 V
      A73-5 (+B) - Body ground Ignition switch ON 11 to 14 V
      H121-17 (IG1) - Body ground Ignition switch ON 11 to 14 V
      H121-20 (IG2) - Body ground Ignition switch ON 11 to 14 V
      H121-19 (ACC) - Body ground Ignition switch ACC 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ENGINE STOP AND START ECU Click here