DTC    C1422    Master Cylinder Pressure Sensor Zero Point High Malfunction

for Preparation Click here


DESCRIPTION

The master cylinder pressure sensor is connected to the skid control ECU in the brake actuator assembly.

C106656E06


DTC Code
DTC Detection Condition
Trouble Area
C1422
When the stop light switch is OFF, the PMC terminal voltage is more than 0.86 V for 5 seconds or more.
  1. Stop light switch
  2. Stop light switch circuit
  3. Master cylinder pressure sensor circuit
  4. Brake actuator assembly (Master cylinder pressure sensor)

WIRING DIAGRAM

Refer to DTC C1425 (Click here).

INSPECTION PROCEDURE

NOTICE:
  1. When replacing the brake actuator assembly, perform zero point calibration (Click here).
  2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT:
When C1425 is output together with C1422, inspect and repair the trouble areas indicated by C1425 first (Click here).

1.CHECK STOP LIGHT OPERATION

  1. Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.

    OK:

    Condition
    		Illumination Condition
    Brake pedal depressed
    		ON
    Brake pedal released
    		OFF



NG
INSPECT STOP LIGHT CIRCUIT (Click here)
OK


2.READ VALUE USING INTELLIGENT TESTER (STOP LIGHT SWITCH)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

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

    ABS/VSC/TRC (Skid Control ECU) 
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    Stop Light SW
    		Stop light switch / ON or OFF
    		ON: Brake pedal depressed
    OFF: Brake pedal released
    		-

  1. Check that the stop light condition observed on the intelligent tester changes according to brake pedal operation.

    OK:
    The intelligent tester displays ON or OFF according to brake pedal operation.



NG
Go to step 5
OK


3.CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION

  1. Turn the ignition switch off.

  1. Check the brake pedal height and stop light switch installation (Click here).

    OK:
    The brake pedal height and stop light switch installation are normal.



NG
ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH (Click here)
OK


4.RECONFIRM DTC

  1. Clear the DTCs (Click here).

  1. Start the engine.

  1. 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).

  1. Check if the same DTC is recorded (Click here).

    Result:

    Result
    		Proceed to
    DTC (C1422) is not output
    		A
    DTC (C1422) is output
    		B



B
REPLACE BRAKE ACTUATOR ASSEMBLY (Click here)
A

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (Click here)  

5.INSPECT SKID CONTROL ECU (STP TERMINAL)


    E175972E08

  1. Turn the ignition switch off.
    Text in illustration 
    *1
    		Front view of wire harness connector
    (to Skid Control ECU)

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

  1. Disconnect the skid control ECU connector.

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

    Standard Voltage:
    for LHD 
    Tester Connection
    		Switch Condition
    		Specified Condition
    A16-2 (STP) - Body ground
    		Stop light switch ON
    (Brake pedal depressed)
    		8 to 14 V
    A16-2 (STP) - Body ground
    		Stop light switch OFF
    (Brake pedal released)
    		Below 1.5 V
    for RHD 
    Tester Connection
    		Switch Condition
    		Specified Condition
    A17-2 (STP) - Body ground
    		Stop light switch ON
    (Brake pedal depressed)
    		8 to 14 V
    A17-2 (STP) - Body ground
    		Stop light switch OFF
    (Brake pedal released)
    		Below 1.5 V



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT)
OK

REPLACE BRAKE ACTUATOR ASSEMBLY (Click here)