ANTI-LOCK BRAKE SYSTEM, Diagnostic DTC:C0273/13, C0274/14

DTC Code DTC Name
C0273/13 Open in ABS Motor Relay Circuit
C0274/14 Short to B+ in ABS Motor Relay Circuit

DESCRIPTION

The ABS motor relay supplies power to the ABS pump motor. While the ABS is activated, the ECU switches the motor relay ON and operates the ABS pump motor.

DTC No. DTC Detecting Condition Trouble Area
C0273/13

Conditions 1. or 2. continue for 0.2 seconds or more.


  1. ECU IG1 terminal voltage is 9.5 V to 18.5 V and during the initial checking or when the motor relay is ON while ABS is operating, the motor relay contact is OFF.

  2. During initial checking with ECU IG1 terminal voltage is less than 9.5 V or when the motor relay is ON during the ABS operation, the motor relay contact does not become ON.

  • ABS motor relay

  • ABS motor relay circuit

  • Battery
C0274/14

Conditions 1. and 2. continue for 4 seconds or more.


  1. When the motor relay is OFF, the condition that the motor relay contact is ON.

  2. When the motor relay is OFF, ECU MT terminal is under the open circuit condition.

WIRING DIAGRAM

A01KFFQE01

INSPECTION PROCEDURE

Tech Tips

Start the inspection from step 1 in case of using the intelligent tester and start from step 2 in case of not using intelligent tester.

PROCEDURE


  1. DO ACTIVE TEST OF INTELLIGENT TESTER (ABS MOTOR RELAY OPERATION)


    1. Select the ACTIVE TEST mode on the intelligent tester.

    2. Check the operation sound of the ABS motor relay when operating it with the intelligent tester.

      OK
      The operation sound of the pump motor should be heard.

    OK

    CHECK CONTINUITY (TERMINAL 5 OF R/B No. 2-MT OF SKID CONTROL ECU) Click here

    NG

  2. CHECK TERMINAL VOLTAGE (TERMINAL 5 OF R/B No. 2)


    1. A01KH10E02
      Text in Illustration
      *1 R/B No. 2

      Remove the ABS motor relay from R/B No. 2.

    2. Measure voltage between terminal 5 of R/B No. 2 (for ABS motor relay) and body ground.

      OK
      Voltage: 10 - 14 V

    NG

    INSPECT FUSE (ABS OF R/B No. 2) Click here

    OK

  3. INSPECT ABS MOTOR RELAY


    1. A01KHO1E01

      Check continuity between each terminal of ABS motor relay.

      OK
      Terminals 1 and 2 Continuity (Reference value 80 Ω)
      Terminals 3 and 5 Open

    2. Apply battery positive voltage between terminals 1 and 2.

    3. A01KGKYE02
      Text in Illustration
      *a Open
      *b Continuity

      Check continuity between terminals 3 and 5 of ABS motor relay.

      OK
      Terminals 3 and 5 Continuity

    NG

    REPLACE ABS MOTOR RELAY

    OK

  4. CHECK CONTINUITY (TERMINAL 5 OF R/B No. 2-MT OF SKID CONTROL ECU)


    1. A01KIDHE02
      Text in Illustration
      *1 ABS MTR Relay
      *2 Skid control ECU
      *3 R/B No. 2
      *4 Brake Actuator

      Disconnect the connector (S6) from the skid control ECU.

    2. Check continuity between terminal 3 of R/B No. 2 (for ABS MTR relay) and terminal MT (S6 - 10) of skid control ECU harness side connector.

      OK
      Continuity

      Tech Tips

      There is resistance of 33 Ω between terminals BM and MT of the brake actuator.


    NG

    REPAIR OR REPLACE HARNESS, CONNECTOR OR RAKE ACTUATOR

    OK

  5. CHECK HARNESS AND CONNECTOR (ABS MOTOR RELAY - SKID CONTROL ECU)


    1. Check for open and short circuit in harness and connector between ABS motor relay and skid control ECU Click here.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK RECONFIRM DTC


    1. Check DTC on page Click here.

      A Malfunction Code
      B Normal Code

    B

    NO PROBLEM

    A

  7. CHECK CONTACT CONDITION


    OK

    CHECK AND REPLACE SKID CONTROL ECU ASSEMBLY

    NG

    CHECK AND REPAIR HARNESS AND CONNECTOR

  8. INSPECT FUSE (ABS OF R/B No. 2)


    1. A01KEGQE02
      Text in Illustration
      *1 R/B No. 2
      *2 ABS

      Remove ABS fuse from the R/B No. 2.

    2. Check continuity of ABS fuse.

      OK
      Continuity

    NG

    REPLACE FUSE

    OK

    CHECK AND REPAIR HARNESS AND CONNECTOR