ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1438/59

DTC Code DTC Name
C1438/59 Lost Communication with HV ECU

DESCRIPTION

The skid control ECU receives signals from the power management control ECU via the CAN communication system.

DTC Code INF Code DTC Detection Condition Trouble Area
C1438/59 154 When IG2 terminal is 9.5 V or more, the signal that indicates the brake data cannot be received from the power management control ECU for 2 seconds or more.

  • CAN communication system (Skid control ECU to power management control ECU)

  • Skid control ECU
↑ 157 When IG2 terminal voltage is 9.5 V or more, the signal that indicates the brake date cannot be received from the power management control ECU once or more within 5 seconds occurs 10 times in succession. ↑

WIRING DIAGRAM

Refer to DTCs U0073/94, U0123/62, U0124/95, U0126/63 and U0293/59 Click here.

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)


    1. Using the intelligent tester, check for any momentary interruption in the wire harness and connector corresponding to the DTC Click here.

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      HV Communication Open Hybrid vehicle communication open detection / Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      OK
      There are no momentary interruptions.

      Tech Tips

      Perform the above inspection before removing the sensor and connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - POWER MANAGEMENT CONTROL ECU) Click here

    OK

  2. RECONFIRM DTC


    1. Turn the power switch off.

    2. Clear the DTCs Click here.

    3. Turn the power switch on (READY).

    4. Drive the vehicle at a speed of 15 km/h (9 mph) or more for 10 seconds or more.

    5. Check that no CAN communication system DTC is output Click here.

    6. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTC (C1438/59) is not output A
      DTC (C1438/59) is output B
      DTC (CAN communication system DTC) is output C

    B

    REPLACE SKID CONTROL ECU Click here

    C

    INSPECT CAN COMMUNICATION SYSTEM Click here

    A

    CHECK FOR INTERMITTENT PROBLEMS Click here

  3. REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - POWER MANAGEMENT CONTROL ECU)


    1. Turn the power switch off.

    2. Repair or replace the harness or connector.

    3. Check for any momentary interruption between the skid control ECU and the power management control ECU Click here.

    4. Check that there is no momentary interruption.


    NEXT

  4. RECONFIRM DTC


    1. Turn the power switch off.

    2. Clear the DTCs Click here.

    3. Turn the power switch on (READY).

    4. Drive the vehicle at a speed of 15 km/h (9 mph) or more for 10 seconds or more.

    5. Check that no CAN communication system DTC is output Click here.

    6. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTC (C1438/59) is not output A
      DTC (C1438/59) is output B
      DTC (CAN communication system DTC) is output C

    B

    REPLACE SKID CONTROL ECU Click here

    C

    INSPECT CAN COMMUNICATION SYSTEM Click here

    A

    END