CAN COMMUNICATION SYSTEM Power Steering ECU Communication Stop Mode

DESCRIPTION

Detection Item Symptom Trouble Area
Power Steering ECU Communication Stop Mode

  • "Power Steering (EPS)" is not displayed on "CAN Bus Check" screen of the GTS.

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

  • Power steering ECU assembly branch wire or connector

  • Power source circuit of power steering ECU assembly

  • Power steering ECU assembly

WIRING DIAGRAM

A00413NE01
A0043N5E01

INSPECTION PROCEDURE

Note


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

  • Turn the power switch off before inspecting CAN bus wires 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 WIRES (POWER STEERING ECU ASSEMBLY BRANCH WIRE)


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

    2. A0043IWE73
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Power Steering ECU)

      Disconnect the L45 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
      L45-1 (CANH) - L45-7 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω

    NG

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

    OK

  2. CHECK HARNESS AND CONNECTOR (GROUND TERMINAL)


    1. A0040Z8E23
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

      Disconnect the A27 power steering ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A27-2 (PGND) - Body ground Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GROUND CIRCUIT)

    OK

  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)


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

    2. A0043IWE74
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      L45-6 (IG) - Body ground Power switch on (IG) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

    OK

    REPLACE POWER STEERING ECU ASSEMBLY Click here