VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1422

DTC Code DTC Name
C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction

DESCRIPTION

DTC No. Detection Item DTC Detection Condition Trouble Area
C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction

When the vehicle speed is 3 km/h (2 mph) or more and stop light switch assembly is OFF, master cylinder pressure continuously exceeds 1.764 MPa (18.0 kgf/cm2, 255 psi) for 5 seconds or more.

  • Stop light switch circuit

  • Wire harness or connector

  • Master cylinder pressure sensor (brake actuator assembly)

  • Skid control ECU (brake actuator assembly)

Tech Tips

for C1422: Even after the trouble areas are repaired, the ABS warning light will not go off unless the following operations are performed.


  1. Turn the engine switch on (IG).

  2. Keep the vehicle stationary for 5 seconds or more and depress the brake pedal lightly 2 or 3 times.

  3. Drive the vehicle at the vehicle speed of 50 km/h (31 mph) and depress and hold the brake pedal firmly for approximately 3 seconds.

  4. Repeat the above operation 3 times or more and check that the ABS warning light goes off.

  5. Clear the DTCs.

WIRING DIAGRAM

Refer to DTC C1425.

Click here

CAUTION / NOTICE / HINT

Note


  • When replacing the skid control ECU (brake actuator assembly), perform zero point calibration and store system information.

    Click here

  • Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE


  1. CHECK DTC


    1. Clear the DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the engine switch off.

    3. Start the engine.

    4. Perform a road test.

    5. Check for DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      DTC C1422 is output. A
      DTCs C1422 and C1425 are output. B

    B

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

    A

  2. READ VALUE USING GTS (STOP LIGHT SWITCH ASSEMBLY)


    1. Select the Data List using the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Stop Light SW Stop light switch assembly ON or OFF

      ON: Brake pedal depressed

      OFF: Brake pedal released

      		 -

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      Stop Light SW

    2. Check that the stop light switch assembly condition observed on the GTS change according to brake pedal operation.

      OK
      The GTS displays ON or OFF according to brake pedal operation.
      Result
      Proceed to
      OK
      NG

    NG

    CHECK BRAKE PEDAL AND STOP LIGHT SWITCH ASSEMBLY INSTALLATION Click here

    OK

  3. READ VALUE USING GTS (MASTER CYLINDER PRESSURE SENSOR)


    1. Select the Data List using the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Master Cylinder Pressure Master cylinder pressure sensor pressure Min.: 0.00 Mpa, Max.: 24.48 Mpa

      Brake pedal depressed: Proportional to pedal force

      Brake pedal released: 0.00 to 1.76 Mpa

      		 -

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      Master Cylinder Pressure
      OK
      Data List pressure is within standard range.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here

    OK

  4. RECONFIRM DTC


    1. Clear the DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the engine switch off.

    3. Start the engine.

    4. Drive the vehicle and perform a braking test (decelerate the vehicle by depressing the brake pedal).

    5. Check if the same DTC is output.

      Click here


      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      DTC C1422 is not output. A
      DTC C1422 is output. B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here

  5. CHECK BRAKE PEDAL AND STOP LIGHT SWITCH ASSEMBLY INSTALLATION


    1. Turn the engine switch off.

    2. Check the brake pedal height and stop light switch assembly installation.

      for LHD: Click here

      for RHD: Click here

      OK
      The brake pedal height and stop light switch assembly installation are normal.
      Result
      Proceed to
      OK
      NG

    NG

    ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH ASSEMBLY for LHD: Click here
    ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH ASSEMBLY for RHD: Click here

    OK

  6. INSPECT STOP LIGHT SWITCH ASSEMBLY


    1. Inspect the stop light switch assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE STOP LIGHT SWITCH ASSEMBLY Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (STP TERMINAL)


    1. B0066Q4C25
      *a

      Front view of wire harness connector

      (to Skid Control ECU (Brake Actuator Assembly))

      Turn the engine switch off.

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

    3. Disconnect the A86 skid control ECU (brake actuator assembly) connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A86-35 (STP) - Body ground Stop light switch assembly on (Brake pedal depressed) 8 to 14 V
      A86-35 (STP) - Body ground Stop light switch assembly off (Brake pedal released) Below 1.5 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT)