VEHICLE STABILITY CONTROL SYSTEM(for Hydraulic Brake Booster), Diagnostic DTC:C1253

DTC Code DTC Name
C1253 Pump Motor Relay

DESCRIPTION

The motor relay (semiconductor relay) is built into the master cylinder solenoid and drives the pump motor based on a signal from the skid control ECU.

DTC Code DTC Detection Condition Trouble Area
C1253 There is a motor system circuit (motor input circuit) malfunction.

  • ABS NO. 1 fuse

  • Motor relay circuit

  • Master cylinder solenoid (Skid control ECU)

WIRING DIAGRAM

B001G46E28

CAUTION / NOTICE / HINT

Note


  • When replacing the master cylinder solenoid, perform calibration Click here.

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

PROCEDURE


  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (MOTOR RELAY)


    1. Turn the ignition switch off.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the intelligent tester on.

    5. Start the engine.

    6. Enter the following menus: Chassis / ABS/VSC/TRC / Active Test.

      ABS/VSC/TRC
      Tester Display Test Part Control Range Diagnostic Note
      Motor Relay Motor relay Relay ON/OFF An operating sound of the motor can be heard.

    7. Check the operating sound of the motor individually when operating it with the intelligent tester.

      OK
      An operating sound of the motor can be heard.

    NG

    CHECK TERMINAL VOLTAGE (+BM1, +BM2) Click here

    OK

  2. RECONFIRM DTC


    1. Clear the DTCs Click here.

    2. Turn the ignition switch off.

    3. Depress the brake pedal more than 40 times.

    4. Turn the ignition switch to ON.

    5. Wait until the pump motor stops.

    6. Depress the brake pedal several times until the pump motor turns on. (Procedure A)

    7. Wait until the pump stops. (Procedure B)

    8. Repeat the above steps (procedure A and B) 3 more times.

    9. Check if the same DTC is output Click here.

      Tech Tips

      Reinstall the sensors, connectors, etc. and restore the previous vehicle conditions before rechecking for DTCs.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output (for LHD) B
      DTC is output (for RHD) C

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

  3. CHECK TERMINAL VOLTAGE (+BM1, +BM2)


    1. Disconnect the A7 and A8 skid control ECU connectors.

    2. B001DSNE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A7-2 (+BM1) - Body ground Always 11 to 14 V
      A8-2 (+BM2) - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (GND1, GND2 AND GND3 TERMINAL)


    1. Disconnect the A7 and A8 skid control ECU connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A7-1 (GND1) - Body ground Always Below 1 Ω
      A7-32 (GND2) - Body ground Always Below 1 Ω
      A8-4 (GND3) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. RECONFIRM DTC


    1. Clear the DTCs Click here.

    2. Turn the ignition switch off.

    3. Depress the brake pedal more than 40 times.

    4. Turn the ignition switch to ON.

    5. Wait until the pump motor stops.

    6. Depress the brake pedal several times until the pump motor turns on. (Procedure A)

    7. Wait until the pump stops. (Procedure B)

    8. Repeat the above steps (procedure A and B) 3 more times.

    9. Check if the same DTC is output Click here.

      Tech Tips

      Reinstall the sensors, connectors, etc. and restore the previous vehicle conditions before rechecking for DTCs.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output (for LHD) B
      DTC is output (for RHD) C

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here