ANTI-LOCK BRAKE SYSTEM, Diagnostic DTC:C0278/11, C0279/12

DTC Code DTC Name
C0278/11 Open in ABS Solenoid Relay Circuit
C0279/12 Short to B+ in ABS Solenoid Relay Circuit

DESCRIPTION

This relay supplies power to each ABS solenoid.

Immediately after the ignition switch is turned to the ON position, the relay turns on if the solenoid is determined to be normal as a result of self-diagnosis during initial check.

The relay turns off if an open/short is detected.

If the voltage supplied to the motor relay (+BS) is below the DTC detection threshold due to low voltage from the battery/alternator, the DTCs may be stored.

DTC No. DTC Detection Condition Trouble Area
C0278/11 With the IG1 terminal voltage 9.5 V or more, the solenoid relay contact is OFF for 0.2 seconds or more immediately after the solenoid relay is turned ON.

  • ABS SOL fuse

  • ABS solenoid relay

  • ABS solenoid relay circuit

  • Brake actuator assembly
C0279/12 The solenoid relay contact is ON for 0.2 seconds or more when the solenoid relay is OFF.

  • ABS SOL fuse

  • ABS solenoid relay

  • ABS solenoid relay circuit

  • Brake actuator assembly

WIRING DIAGRAM

Refer to DTC C0226/21, C0236/22, and C0246/23 Click here.

INSPECTION PROCEDURE

PROCEDURE


  1. INSPECT FUSE (ABS SOL FUSE)


    1. A003GU2E02

      Remove the ABS SOL fuse from the No. 2 engine room relay block.

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

      Standard resistance
      Tester Connection Specified Condition
      ABS SOL (25 A) fuse Below 1 Ω (Continuity)

    NG

    REPLACE FUSE (ABS SOL FUSE)

    OK

  2. INSPECT SKID CONTROL ECU (+BS TERMINAL VOLTAGE)


    1. A003DPCE12

      Install the ABS SOL fuse.

    2. Disconnect the skid control ECU connector.

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

      Standard voltage
      Tester Connection Condition Specified Condition
      B19-1 (+BS) - Body ground Always 10 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (+BS CIRCUIT)

    OK

  3. INSPECT SKID CONTROL ECU (GND TERMINAL CONTINUITY)


    1. A003DPCE29

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

      Standard resistance
      Tester Connection Specified Condition
      B19-2 (GND) - Body ground Below 1 Ω
      B19-24 (GND) - Body ground Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)

    OK

  4. RECONFIRM DTC


    1. Clear the DTCs Click here.

    2. Start the engine.

    3. Drive the vehicle at the speed of 4 mph (6 km/h) or more.

    4. Check that the same DTCs are recorded Click here.

      Tech Tips


      • Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.

      • If a speed signal of 4 mph (6 km/h) or more is input to the skid control ECU, with the ignition switch on and the stop light switch off, the ECU performs self-diagnosis of the motor and solenoid circuits.

      Result
      Condition Proceed to
      DTCs (C0278/11 and C0279/12) are output A
      DTCs (C0278/11 and C0279/12) are not output B

      Tech Tips


      • If any DTCs are output while jiggling a connector or wire harness of the brake actuator (skid control ECU), inspect and repair the connector or wire harness.

      • If the normal system code is output, slightly jiggle the connectors, wire harnesses, and fuses of the brake actuator assembly. Make sure that no DTCs are output.

      • These DTCs may be memorized due to a malfunction in the connector terminal connection, etc.


    B

    END

    A

    REPLACE BRAKE ACTUATOR ASSEMBLY