POWER STEERING SYSTEM, Diagnostic DTC:C1566

DTC Code DTC Name
C1566 Lost Communication with PSOK Signal of DC / DC Converter

DESCRIPTION

Base on the WDD signal (power steering converter condition notification signal) from the power steering converter assembly, the power steering ECU performs various processes. Based on the PSOK signal (EPS assist permission signal) from the hybrid vehicle control ECU, the power steering converter supplies a high voltage power supply to the power steering ECU. As a fail-safe function, while the system is malfunctioning, power assistance is stopped.

DTC Code Detection Condition Trouble Area
C1566 PSOK signal communication malfunction

  • Hybrid control system

  • Harness or connector

  • Power steering converter assembly

  • Power steering ECU

WIRING DIAGRAM

A000WC1E10

PROCEDURE


  1. CHECK DTC (HYBRID CONTROL SYSTEM)


    1. Check for DTCs in the hybrid control system Click here.

      Result
      Result Proceed to
      P3086-184 or P3087-183 is not output A
      P3086-184 or P3087-183 is output B

    B

    GO TO HYBRID CONTROL SYSTEM (DIAGNOSTIC TROUBLE CODE CHART) Click here

    A

  2. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - POWER STEERING CONVERTER)


    1. Disconnect the A77 hybrid vehicle control ECU connector.

      A000WULE01
      *1 Front view of wire harness connector: (to Hybrid Vehicle Control ECU)
      *2 Front view of wire harness connector: (to Power Steering Converter)
      *3 PSOK
      *4 DDOK

    2. Disconnect the n1 power steering converter connector.

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

      Standard resistance
      Tester Connector Condition Specified Condition
      A77-21 (PSOK) - n1-6 (DDOK) Always Below 1 Ω
      A77-21 (PSOK) or n1-6 (DDOK) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (POWER STEERING CONVERTER POWER SUPPLY)


    1. Reconnect the A77 hybrid vehicle control ECU connector.

    2. A000ZTRE02
      *1 Component with harness connected: (Power Steering Converter)

      Reconnect the n1 power steering converter connector.

    3. Turn the power switch ON (IG).

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

      Standard voltage
      Tester Connector Switch Condition Specified Condition
      n1-5 (IG) - Body ground Power switch ON (IG) 11 to 14 V

    5. Turn the power switch OFF.

    6. Disconnect the n2 power steering converter connector.

    7. A000XY5E02
      *1 Front view of wire harness connector: (to Power Steering Converter)

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

      Standard resistance
      Tester Connector Condition Specified Condition
      n2-2 (VGND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK POWER STEERING CONVERTER (OPERATION)


    1. Temporarily replace the power steering converter with a new or normally functioning one Click here.


    NEXT

  5. CHECK DTC (POWER STEERING SYSTEM)


    1. Check for DTCs in the power steering system Click here.

      Result
      Result Proceed to
      DTC C1566 is not output A
      DTC C1566 is output B

    A

    END

    B

    REPLACE HYBRID VEHICLE CONTROL ECU Click here