VEHICLE STABILITY CONTROL SYSTEM, 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 No.

Detection Item

DTC Detection Condition

Trouble Area

C1253

Pump Motor Relay

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

C173280E06

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 engine switch off.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the engine switch on (IG).

    4. Turn the intelligent tester on.

    5. Start the engine.

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

      Chassis > ABS/VSC/TRC > Active Test

      Tester Display

      Measurement Item

      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.

      Result

      Result

      OK

      NG
    NG

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

    OK

  2. RECONFIRM DTC

    1. Clear the DTCs.

      Click here

      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the engine switch off.

    3. Depress the brake pedal more than 40 times.

    4. Turn the engine switch on (IG).

    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

      Tip:

      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

      B

      Chassis > ABS/VSC/TRC > Trouble Codes

    A

    USE SIMULATION METHOD TO CHECK

    Click here

    B

    REPLACE MASTER CYLINDER SOLENOID

    Click here

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

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

    2. C223567C01

      *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

      Result

      Result

      OK

      NG
    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

      Result

      Result

      OK

      NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. RECONFIRM DTC

    1. Clear the DTCs.

      Click here

      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the engine switch off.

    3. Depress the brake pedal more than 40 times.

    4. Turn the engine switch on (IG).

    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

      Tip:

      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

      B

      Chassis > ABS/VSC/TRC > Trouble Codes

    A

    USE SIMULATION METHOD TO CHECK

    Click here

    B

    REPLACE MASTER CYLINDER SOLENOID

    Click here