VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1422

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

DESCRIPTION

Refer to DTCs C1281, C1421, C1423 and C1424.

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DTC No. Detection Item DTC Detection Condition Trouble Area
C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction When the stop light switch is OFF, the PMC terminal voltage is more than 0.86 V for 5 seconds or more while the vehicle is being driven at a speed of 3 km/h (2 mph) or more.

  • STOP fuse

  • Stop light switch assembly

  • Stop light switch circuit

  • Skid control ECU (Brake actuator assembly)

  • Brake actuator assembly (Master cylinder pressure sensor)

WIRING DIAGRAM

Refer to DTC C1425.

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CAUTION / NOTICE / HINT

Note


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

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

PROCEDURE


  1. CHECK DTC


    1. Check the DTC C1380 (w/ Stop Light control Relay) or C1425 is output.

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      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      DTC C1380 (w/ Stop Light control Relay) or C1425 is not output A
      DTCs C1422 and C1380 are output (w/ Stop Light control Relay) B
      DTCs C1422 and C1425 are output C

    B

    GO TO DTC CHART Click here

    C

    GO TO DTC CHART Click here

    A

  2. READ VALUE USING GTS (STOP LIGHT SW, MASTER CYLINDER SENSOR)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Chassis / ABS/VSC/TRC / Data List.

    5. In accordance with the display on the GTS, read the Data List.


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

      OFF: Brake pedal released

      ON: Brake pedal depressed

      		 -
      Master Cylinder Sensor Master cylinder pressure sensor reading Min.: 0 V, Max.: 5 V Brake pedal released: 0.3 to 0.9 V Reading increases when brake pedal is depressed.

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      Stop Light SW
      Master Cylinder Sensor
      Standard Voltage
      Master cylinder pressure sensor reading is 0.86 V or less at the instant the stop light switch changes from off to on.
      Result
      Proceed to
      OK
      NG

    NG

    CHECK BRAKE PEDAL AND STOP LIGHT SWITCH ASSEMBLY INSTALLATION Click here

    OK

  3. RECONFIRM DTC


    1. Clear the DTCs.

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      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Start the engine.

    3. Drive the vehicle at a speed of 40 km/h (25 mph) or more and perform braking test (decelerate the vehicle by depressing the brake pedal).

    4. Check if the same DTC is recorded.

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

    DTC C1422 is not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC C1422 is output

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

  4. CHECK BRAKE PEDAL AND STOP LIGHT SWITCH ASSEMBLY INSTALLATION


    1. Turn the ignition switch off.

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

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      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 Click here

    OK

  5. INSPECT STOP LIGHT SWITCH ASSEMBLY


    1. Remove the stop light switch assembly.

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    2. Inspect the stop light switch assembly.

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      Result
      Proceed to
      OK
      NG

    NG

    REPLACE STOP LIGHT SWITCH ASSEMBLY Click here

    OK

  6. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - STOP LIGHT SWITCH ASSEMBLY)


    1. Disconnect the A64 skid control ECU (brake actuator assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A64-2 (STP) - A5-1 Always Below 1 Ω
      A64-2 (STP) or A5-1 - Body ground Always 10 kΩ or higher
      A64-22 (STP2) - A5-1* Always Below 1 Ω
      A64-22 (STP2) or A5-1 - Body ground* Always 10 kΩ or higher

      • *: w/ Stop Light Control Relay

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR