ANTI-LOCK BRAKE SYSTEM, Diagnostic DTC:C1251/51

DTC Code DTC Name
C1251/51 Open in Pump Motor Circuit

DESCRIPTION

The ABS pump motor is located inside the brake actuator.

DTC No. DTC Detection Condition Trouble Area
C1251/51

When one of following conditions is met:


  • Actuator pump motor does not operate properly

  • Actuator pump motor circuit remains open for at least 2 seconds

  • Brake actuator

  • Brake actuator circuit

WIRING DIAGRAM

A01J5BSE02

INSPECTION PROCEDURE

PROCEDURE


  1. CHOOSE DIAGNOSIS METHOD


    1. Choose the diagnosis method.

      Method
      Method Proceed to
      Using intelligent tester A
      Not using intelligent tester B

    B

    CHECK WIRE HARNESS (SKID CONTROL ECU - BATTERY AND BODY GROUND) Click here

    A

  2. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (ABS MOTOR RELAY)


    1. Select the Active Test, generate a control command, and then check that the ABS motor relay operates.

      Skid control ECU:
      Item Vehicle Condition / Test Details Diagnostic Note
      ABS Motor Relay Turn ABS motor relay ON / OFF Operation sound of motor can be heard
      OK
      Operation sound of ABS motor is heard.

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY

    NG

  3. CHECK WIRE HARNESS (SKID CONTROL ECU - BATTERY AND BODY GROUND)

    A01J3N2E06

    1. Disconnect the S2 ECU connector.

    2. Measure the resistance of the wire harness side connector.

      Standard resistance
      Tester Connection Specified Condition
      S2-2 (GND1) - Body ground Below 1 Ω
      S2-24 (GND2) - Body ground Below 1 Ω

    3. Measure the voltage of the wire harness side connector.

      Standard voltage
      Tester Connection Specified Condition
      S2-23 (+BM) - Body ground 10 to 14 V

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY