ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1246/46, C1281/81, C1364/61

DTC Code DTC Name
C1246/46 Master Cylinder Pressure Sensor Malfunction
C1281/81 Master Cylinder Pressure Sensor Output Malfunction (Test Mode DTC)
C1364/61 Wheel Cylinder Pressure Sensor Malfunction

DESCRIPTION

The regulator pressure sensor and wheel cylinder pressure sensor are built into the brake actuator. They measure their respective pressures and send signals to the skid control ECU (brake booster with master cylinder assembly).

DTC C1281/81 will be cleared when the regulator pressure sensor sends a regulator pressure signal or when Test Mode ends. DTC C1281/81 is output only in Test Mode.

DTC No. Detection Item INF Code DTC Detection Condition Trouble Area Note
C1246/46 Master Cylinder Pressure Sensor Malfunction

201

202

203

204

207

  • INF Code: 201


    • Sensor supply voltage (VCM1) is 4.75 V or less, or 5.25 V or more for 0.05 seconds.

  • INF Code: 202


    • Regulator pressure sensor output voltage (Preg) is less than 8%, or 90.3% or more (less than 0.4 V, or 4.52 V or more) of sensor supply voltage (VCM1) for 0.05 seconds or more.

  • INF Code: 203


    • When not under braking, the regulator pressure sensor output voltage is 0.2 V or less or 0.88 V or more for 3 seconds or more.

  • INF Code: 204


    • Either of the following is detected:


      1. The regulator pressure sensor output voltage does not correspond with brake pedal stroke sensor assembly and the readings remain out of specification for 0.5 to 5 seconds or more continuously.

        (The brake pedal stroke sensor assembly may be malfunctioning.)

      2. The regulator pressure sensor output voltage does not correspond with wheel cylinder pressure sensor and the outputs remain out of specification for 0.5 to 5 seconds or more continuously.

        (May be output with INF code 424.)

  • INF Code: 207


    • Fluctuation of regulator pressure sensor output is out of specification (the difference between the present value and last value is 15 MPa (153.0 kgf/cm2, 2176 psi) or more) for 0.1 seconds or more.

  • INF Code: 201, 202, 203, 207


    • Brake booster with master cylinder assembly

  • INF Code: 204


    • Brake pedal stroke sensor assembly

    • Brake booster with master cylinder assembly

 Electronically controlled brake system DTC
C1281/81 Master Cylinder Pressure Sensor Output Malfunction (Test Mode DTC) - Detected only during Test Mode.

  • Stop light switch assembly

  • Regulator pressure sensor (Brake booster with master cylinder assembly)

 ABS Test Mode DTC
C1364/61 Wheel Cylinder Pressure Sensor Malfunction

421

422

423

424

426

  • INF Code: 421


    • Sensor supply voltage 1 (VCM1) is 4.75 V or less, or 5.25 V or more for 0.05 seconds or more.

  • INF Code: 422


    • Wheel cylinder pressure sensor output voltage (Pfront) is less than 8%, or 90.3% or more (less than 0.4 V, or 4.52 V or more) of sensor supply voltage (VCM1) for 0.05 seconds or more.

  • INF Code: 423


    • When not under braking, the wheel cylinder pressure sensor output voltage is 0.2 V or less or 0.88 V or more for 0.1 to 3 seconds or more.

  • INF Code: 424


    • The wheel cylinder pressure sensor output voltage does not correspond with regulator pressure sensor and the outputs remain out of specification for 0.5 to 5 seconds or more continuously.

      (May be output with INF code 204.)

  • INF Code: 426


    • Fluctuation of wheel cylinder pressure sensor output is out of specification (the difference between the present value and last value is 15 MPa (153.0 kgf/cm2, 2176 psi) or more) for 0.1 seconds or more.

 Brake booster with master cylinder assembly Electronically controlled brake system DTC

CAUTION / NOTICE / HINT

Note

When replacing the skid control ECU (brake booster with master cylinder assembly) or brake actuator (brake booster with master cylinder assembly), perform initialization and calibration of the linear solenoid valve.

Click here

PROCEDURE


  1. CHECK STOP LIGHT SWITCH ASSEMBLY INSTALLATION


    1. Check the protrusion of the plunger.

      Click here

      OK
      The stop light switch assembly is installed properly.

      Tech Tips

      If the stop light switch assembly is not installed properly, adjust the protrusion of the plunger before proceeding to the next step.

      Result
      Proceed to
      OK
      NG

    NG

    ADJUST PROTRUSION OF SHAFT Click here

    OK

  2. READ VALUE USING GTS (REGULATOR PRESSURE SENSOR)


    1. Mount a pedal effort gauge and install LSPV gauges to the rear wheels.

      Click here

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Select the Data List on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Regulator Pressure Sensor Output Regulator pressure sensor output Min.: 0.00 V, Max.: 5.00 V Brake pedal released: 0.10 to 0.90 V Reading increases when brake pedal is depressed

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      Regulator Pressure Sensor Output

    5. Check the output value of the regulator pressure sensor as the brake pedal is depressed.

      Standard Voltage

      Brake Effort

      (N (kgf, lbf))

      Regulator Pressure Sensor Output

      (V)

      Rear Right Wheel Hydraulic Pressure

      (MPa (kgf/cm2, psi))

      Rear Left Wheel Hydraulic Pressure

      (MPa (kgf/cm2, psi))
      100 (10, 22.5) 1.50 to 2.30

      4.88 to 8.88 MPa (49.8 to 90.6 kgf/cm2, 708 to 1288 psi)

      4.88 to 8.88 MPa (49.8 to 90.6 kgf/cm2, 708 to 1288 psi)
      200 (20, 45.0) 3.37 to 4.17

      14.01 to 18.01 MPa (142.9 to 183.7 kgf/cm2, 2031 to 2611 psi)

      14.01 to 18.01 MPa (142.9 to 183.7 kgf/cm2, 2031 to 2611 psi)
      Result
      Result Proceed to
      OK A
      NG (for RHD) B
      NG (for LHD) C

    B

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

    C

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

    A

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


    1. Install LSPV gauges to the front wheels.

      Click here

    2. Select the Data List on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Wheel Cylinder Pressure Sensor Wheel cylinder pressure sensor Min.: 0.00 V, Max.: 5.00 V Brake pedal released: 0.10 to 0.90 V Reading increases when brake pedal is depressed

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      Wheel Cylinder Pressure Sensor

    3. Check the output values of the wheel cylinder pressure sensor at each hydraulic pressure during electronically controlled brake system control.

      Standard Voltage
      for Front Wheel Cylinder LH

      Hydraulic Pressure

      (MPa (kgf/cm2, psi))

      Wheel Cylinder Pressure Sensor

      (V)
      2.0 (20.4, 290) 0.53 to 1.33
      5.0 (51.0, 725) 1.12 to 1.92
      7.0 (71.4, 1015) 1.52 to 2.32
      10.0 (102.0, 1451) 2.14 to 2.94
      for Front Wheel Cylinder RH

      Hydraulic Pressure

      (MPa (kgf/cm2, psi))

      Wheel Cylinder Pressure Sensor

      (V)
      2.0 (20.4, 290) 0.53 to 1.33
      5.0 (51.0, 725) 1.12 to 1.92
      7.0 (71.4, 1015) 1.52 to 2.32
      10.0 (102.0, 1451) 2.14 to 2.94
      Result
      Result Proceed to
      OK A
      NG (for RHD) B
      NG (for LHD) C

    B

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

    C

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

    A

  4. READ VALUE USING GTS (BRAKE PEDAL STROKE SENSOR ASSEMBLY AND PRESSURE SENSOR COMPARISON)


    1. Mount a pedal effort gauge and install LSPV gauges to the front and rear wheels.

      Click here

    2. Select the Data List on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Regulator Pressure Sensor Output Regulator pressure sensor output Min.: 0.00 V, Max.: 5.00 V Brake pedal released: 0.10 to 0.90 V Reading increases when brake pedal is depressed
      Stroke Sensor Brake pedal stroke sensor assembly Min.: 0.00 V, Max.: 5.00 V Brake pedal released: 0.65 to 1.35 V Reading increases when brake pedal is depressed
      Stroke Sensor2 Brake pedal stroke sensor assembly 2 Min.: 0.00 V, Max.: 5.00 V Brake pedal released: 3.65 to 4.35 V Reading decreases when brake pedal is depressed
      Wheel Cylinder Pressure Sensor Wheel cylinder pressure sensor Min.: 0.00 V, Max.: 5.00 V Brake pedal released: 0.10 to 0.90 V Reading increases when brake pedal is depressed

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      Regulator Pressure Sensor Output
      Stroke Sensor
      Stroke Sensor2
      Wheel Cylinder Pressure Sensor

    3. Check the output value of the brake pedal stroke sensor assembly as the brake pedal is depressed.

      Standard Voltage

      Brake Effort

      (N (kgf, lbf))

      Stroke Sensor

      (V)

      Stroke Sensor2

      (V)

      Regulator Pressure Sensor Output

      (V)

      Wheel Cylinder Pressure Sensor

      (V)
      100 (10, 22.5) 1.26 to 1.96 3.04 to 3.74 1.50 to 2.30 1.30 to 2.10
      200 (20, 45.0) 1.74 to 2.44 2.56 to 3.26 3.37 to 4.17 2.89 to 3.69
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE BRAKE PEDAL STROKE SENSOR ASSEMBLY Click here

    OK

  5. RECONFIRM DTC


    1. Clear the DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the power switch off.

    3. Perform a road test.

    4. Check if the same DTC is output.

      Click here


      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      DTCs C1246/46 and C1364/61 are not output. A
      DTCs C1246/46 and/or C1364/61 are output (for RHD). B
      DTCs C1246/46 and/or C1364/61 are output (for LHD). C

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

    C

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here