ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1234/34, C1243/43, C1244/44, C1245/45, C1279/79, C1381/97

DTC Code DTC Name
C1234/34 Yaw Rate Sensor Malfunction
C1243/43 Acceleration Sensor Stuck Malfunction
C1244/44 Open or Short in Acceleration Sensor Circuit
C1245/45 Acceleration Sensor Output Malfunction
C1279/79 Acceleration Sensor Output Voltage Malfunction (Test Mode DTC)
C1381/97 Acceleration Sensor Power Supply Voltage Malfunction

DESCRIPTION

The skid control ECU receives signals from the yaw rate and acceleration sensor (airbag sensor assembly) via the CAN communication system.

The airbag sensor assembly has a built-in yaw rate and acceleration sensor and detects the vehicle's condition using 2 circuits (GL1, GL2).

If there are any problems in the bus lines between the yaw rate and acceleration sensor (airbag sensor assembly) and the CAN communication system, DTCs U0123/62 (Lost Communication with Yaw Rate Sensor Module) and U0124/95 (Lost Communication with Lateral Acceleration Sensor Module) are stored.

These DTCs are also output when calibration has not been completed.

DTC C1279/79 will be cleared when the yaw rate and acceleration sensor (airbag sensor assembly) sends a yaw rate and/or acceleration signal or when Test Mode ends. DTC C1279/79 is output only in Test Mode.

DTC No. INF Code DTC Detection Condition Trouble Area
C1234/34 711 While yaw rate sensor communication is enabled, a malfunction signal output is received during the sensor self-check (Sensor 1 (GL1) malfunction). Yaw rate and acceleration sensor (Airbag sensor assembly) internal malfunction
↑ 712 While yaw rate sensor communication is enabled, a malfunction signal output is received during the sensor self-check (Sensor 2 (GL2) malfunction). ↑
↑ 713 While yaw rate sensor communication is enabled, a malfunction signal output is received during the sensor self-check (Zero point calibration malfunction). ↑
↑ 714 While yaw rate sensor communication is enabled, a malfunction signal output is received during the sensor self-check (Two-value comparison malfunction). ↑
C1243/43 561 An acceleration sensor malfunction occurs 16 times or more when the vehicle speed drops from above 30 km/h (19 mph) to 0 km/h (0 mph). Yaw rate and acceleration sensor (Airbag sensor assembly) internal stuck malfunction
↑

562

563

564

 A stuck acceleration sensor value is determined. ↑
C1244/44 571

Either of the following is detected:


  1. Difference between GL1 and GL2 does not become less than 0.4 G for 60 seconds or more after reaching 0.6 G when the vehicle is stopped.

  2. A malfunction signal from the acceleration sensor is received.

  • Yaw rate and acceleration sensor (Airbag sensor assembly) installed improperly

  • Yaw rate and acceleration sensor (Airbag sensor assembly)
C1245/45 581 Difference between longitudinal G calculated from the acceleration sensor value and that calculated from the vehicle speed exceeds 0.35 G for 60 seconds or more.

  • Yaw rate and acceleration sensor (Airbag sensor assembly) installed improperly

  • Yaw rate and acceleration sensor (Airbag sensor assembly)
C1381/97 601 While yaw rate and acceleration sensor communication is enabled, a supply voltage malfunction signal is received from the sensor for 10 seconds.

  • Yaw rate and acceleration sensor (Airbag sensor assembly) supply voltage shut down

  • Yaw rate and acceleration sensor (Airbag sensor assembly)

  • Skid control ECU (Brake booster with master cylinder assembly)
C1279/79 - Detected only during Test Mode.

  • Sensor installation

  • Yaw rate and acceleration sensor (Airbag sensor assembly)

WIRING DIAGRAM

A01I2V7E04

INSPECTION PROCEDURE

Note

When replacing the yaw rate and acceleration sensor (airbag sensor assembly), perform zero point calibration Click here.

Tech Tips

When U0123/62 and/or U0124/95 is output together with C1234/34, C1243/43, C1244/44, C1245/45, and/or C1381/97, inspect and repair the trouble areas indicated by U0123/62 and/or U0124/95 first Click here.

PROCEDURE


  1. CHECK DTC


    1. Clear the DTCs Click here.

    2. Turn the power switch off.

    3. Turn the power switch on (READY).

    4. Drive the vehicle at a speed of 30 km/h (19 mph) or more, turn the steering wheel, and decelerate (depress the brake pedal) the vehicle.

    5. Turn the power switch on (IG) again and check that no CAN communication system DTC is output Click here.

    6. Check if DTC C1210/36 (Zero Point Calibration of Yaw Rate Sensor Undone) or C1336/98 (Zero Point Calibration of Acceleration Sensor Undone) is output Click here.

      Result
      Result Proceed to
      DTCs (C1210/36, C1336/98 and CAN communication system DTC) are not output. A
      CAN communication system DTC is output. B
      DTCs C1210/36 and/or C1336/98 are output. C

    B

    INSPECT CAN COMMUNICATION SYSTEM Click here

    C

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

    A

  2. CHECK AIRBAG SENSOR ASSEMBLY INSTALLATION


    1. Turn the power switch off.

    2. Check that the yaw rate and acceleration sensor (airbag sensor assembly) has been installed properly Click here.

      OK
      The sensor is tightened to the specified torque.
      The sensor is not tilted.

    NG

    INSTALL AIRBAG SENSOR ASSEMBLY CORRECTLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (IG2 TERMINAL)


    1. A01I5F3E05
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Yaw Rate and Acceleration Sensor (Airbag Sensor Assembly))

      Make sure that there is no looseness at the locking part and the connecting part of the connector.

    2. Disconnect the yaw rate and acceleration sensor (airbag sensor assembly) connector.

    3. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      I47-21 (IG2) - Body ground Power switch on (IG) 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IG2 CIRCUIT)

    OK

  4. CHECK HARNESS AND CONNECTOR (E TERMINAL)


    1. A01I5F3E06
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Yaw Rate and Acceleration Sensor (Airbag Sensor Assembly))

      Turn the power switch off.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I47-25 (E1) - Body ground Always Below 1 Ω
      I47-26 (E2) - Body ground Always Below 1 Ω

      Note

      Check the yaw rate and acceleration sensor signal after replacement Click here.

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (E CIRCUIT)

    OK

    REPLACE AIRBAG SENSOR ASSEMBLY Click here