CAN COMMUNICATION SYSTEM(for RHD) Power Steering ECU Communication Stop Mode

DESCRIPTION

Detection Item Symptoms Trouble Area
Power Steering ECU Communication Stop Mode

Either condition is met:


  • "Power Steering (EPS)" is not displayed on "CAN Bus Check".

    Click here

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

    Click here


  • Power source circuit of power steering ECU assembly

  • Power steering ECU assembly ground circuit

  • Power steering ECU assembly CAN branch wire or connector

  • Power steering ECU assembly

  • ECU wire sub-assembly

  • Engine stop and start ECU

WIRING DIAGRAM

Figure 1. w/o Stop and Start System

B008HZ7E08

Figure 2. w/ Stop and Start System

B008J9RE02
B008HZ7E09

CAUTION / NOTICE / HINT

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

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

  • DTC check procedure: Turn the engine switch on (IG) and wait at least 12 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 VEHICLE TYPE


    1. Check vehicle type.

      Result
      Result Proceed to
      for Power Tilt and Power Telescopic Steering Column A
      for Manual Tilt and Manual Telescopic Steering Column B

    B

    CHECK FOR OPEN IN CAN BUS WIRE (POWER STEERING ECU ASSEMBLY BRANCH WIRE) Click here

    A

  2. CHECK FOR OPEN IN CAN BUS WIRE (POWER STEERING ECU ASSEMBLY BRANCH WIRE)


    1. B008IL5C29
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

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

    2. Disconnect the power steering ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      n2-7 (CANH) - n2-8 (CANL) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Result
      Proceed to
      OK
      NG

    NG

    CHECK FOR OPEN IN CAN BUS WIRE (POWER STEERING ECU ASSEMBLY BRANCH WIRE) Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (BATTERY - ECU WIRE SUB-ASSEMBLY)


    1. B008J23C08
      *a

      Front view of wire harness connector

      (to ECU Wire Sub-assembly)

      Reconnect 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 ECU wire sub-assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      An1-1 (PIG) - Body ground Always 9 to 16 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (BATTERY - ECU WIRE SUB-ASSEMBLY)


    1. B008GTBC08
      *a

      Front view of wire harness connector

      (to ECU Wire Sub-assembly)

      Disconnect the ECU wire sub-assembly connector.

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

      Standard Voltage
      w/o Stop and Start System
      Tester Connection Switch Condition Specified Condition
      nl1-5 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      w/ Stop and Start System
      Tester Connection Switch Condition Specified Condition
      nl1-5 (IG) - Body ground Engine switch on (IG) 10.5 to 16 V
      Result
      Result Proceed to
      OK A
      NG (w/o Stop and Start System) B
      NG (w/ Stop and Start System) C

    B

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    C

    CHECK HARNESS AND CONNECTOR (ECU WIRE SUB-ASSEMBLY - ENGINE STOP AND START ECU) Click here

    A

  5. CHECK ECU WIRE SUB-ASSEMBLY


    1. B008I8IC01
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

      Reconnect the ECU wire sub-assembly connectors.

    2. Disconnect the power steering ECU assembly connectors.

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

      Standard Voltage
      w/o Stop and Start System
      Tester Connection Condition Specified Condition
      n2-1 (IG) - Body ground Engine switch on (IG) 8 to 16 V
      n1-1 (PIG) - Body ground Always 9 to 16 V
      w/ Stop and Start System
      Tester Connection Condition Specified Condition
      n2-1 (IG) - Body ground Engine switch on (IG) 10.5 to 16 V
      n1-1 (PIG) - Body ground Always 9 to 16 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      n1-2 (PGND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POWER STEERING ECU ASSEMBLY Click here

    NG

    REPLACE ECU WIRE SUB-ASSEMBLY Click here

  6. CHECK FOR OPEN IN CAN BUS WIRE (POWER STEERING ECU ASSEMBLY BRANCH WIRE)


    1. B008GTBC05
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

      Disconnect the ECU wire sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      nl1-1 (CANH) - nl1-2 (CANL) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE ECU WIRE SUB-ASSEMBLY Click here

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (POWER STEERING ECU ASSEMBLY)

  7. CHECK HARNESS AND CONNECTOR (ECU WIRE SUB-ASSEMBLY - ENGINE STOP AND START ECU)


    1. Disconnect the I57 engine stop and start ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      nl1-5 (IG) - I57-12 (IGO1) Always Below 1 Ω
      nl-5 (IG) or I57-12 (IGO1) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STOP AND START SYSTEM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  8. CHECK FOR OPEN IN CAN BUS WIRE (POWER STEERING ECU ASSEMBLY BRANCH WIRE)


    1. B008HCBC01
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

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

    2. Disconnect the power steering ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      n3-4 (CANH) - n3-8 (CANL) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Result
      Proceed to
      OK
      NG

    NG

    CHECK FOR OPEN IN CAN BUS WIRE (POWER STEERING ECU ASSEMBLY BRANCH WIRE) Click here

    OK

  9. CHECK HARNESS AND CONNECTOR (BATTERY - ECU WIRE SUB-ASSEMBLY)


    1. B008J23C08
      *a

      Front view of wire harness connector

      (to ECU Wire Sub-assembly)

      Reconnect 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 ECU wire sub-assembly connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      An1-1 (PIG) - Body ground Always 9 to 16 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. CHECK HARNESS AND CONNECTOR (BATTERY - ECU WIRE SUB-ASSEMBLY)


    1. B008GTBC08
      *a

      Front view of wire harness connector

      (to ECU Wire Sub-assembly)

      Disconnect the ECU wire sub-assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      nl1-5 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  11. CHECK ECU WIRE SUB-ASSEMBLY


    1. B008J20C01
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

      Reconnect the ECU wire sub-assembly connectors.

    2. Disconnect the power steering ECU assembly connectors.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      n3-1 (IG) - Body ground Engine switch on (IG) 8 to 16 V
      n1-1 (PIG) - Body ground Always 9 to 16 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      n1-2 (PGND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE POWER STEERING ECU ASSEMBLY Click here

    NG

    REPLACE ECU WIRE SUB-ASSEMBLY Click here

  12. CHECK FOR OPEN IN CAN BUS WIRE (POWER STEERING ECU ASSEMBLY BRANCH WIRE)


    1. B008GTBC05
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

      Disconnect the ECU wire sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      nl1-1 (CANH) - nl1-2 (CANL) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE ECU WIRE SUB-ASSEMBLY Click here

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (POWER STEERING ECU ASSEMBLY)