VEHICLE STABILITY CONTROL SYSTEM (for Hydraulic Brake Booster), Diagnostic DTC:C0278, C0279

DTC Code DTC Name
C0278 Open in ABS Solenoid Relay Circuit
C0279 Short in ABS Solenoid Relay Circuit

DESCRIPTION

The solenoid relay is built into the master cylinder solenoid.

This relay supplies power to each solenoid. If the initial check is OK, after the ignition switch is turned to ON, the relay turns on.

DTC Code DTC Detection Condition Trouble Area
C0278

Either condition is met:


  1. Both of the following conditions continue for at least 0.2 seconds.


    1. IG voltage is between 9.5 and 17 V.

    2. The relay contact is open when the relay is on.

  2. Both of the following conditions continue for at least 0.2 seconds.


    1. IG voltage is 9.5 V or less when the relay is on.

    2. The relay contact remains open.

  • ABS NO. 2 fuse

  • Solenoid relay circuit

  • Master cylinder solenoid
C0279

The following condition continues for at least 0.2 seconds.


  • The relay contact is closed immediately after turning the ignition switch to ON when the relay is off.

WIRING DIAGRAM

Refer to DTCs C0226, C0236, C0246, C0256, C1225, C1226, C1227 and C1228 Click here.

INSPECTION PROCEDURE

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. CHECK TERMINAL VOLTAGE (+BS)


    1. Disconnect the A7 skid control ECU connector.

    2. A00O4C5E27
      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
      A7-31 (+BS) - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. 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

  3. RECONFIRM DTC

    Tech Tips

    These codes are stored when a problem is detected in the master cylinder solenoid.

    The solenoid relay is in the master cylinder solenoid.

    Therefore, solenoid relay circuit inspections and relay unit inspections cannot be performed. Be sure to check if any DTC is output before replacing the master cylinder solenoid.


    1. Clear the DTCs Click here.

    2. Drive the vehicle at a speed of approximately 32 km/h (20 mph) or more for 60 seconds or more.

    3. Check if the same DTCs are 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

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

    A

    USE SIMULATION METHOD TO CHECK Click here