Dtc C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING INTELLIGENT TESTER (STOP LIGHT SW)

CHECK BRAKE PEDAL AND STOP LIGHT SWITCH ASSEMBLY INSTALLATION

RECONFIRM DTC

CHECK TERMINAL VOLTAGE AND RESISTANCE (STOP LIGHT SWITCH ASSEMBLY POWER SOURCE TERMINAL)

CHECK TERMINAL VOLTAGE (STP)

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

DTC C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction


DESCRIPTION

Refer to DTCs C1421, C1423 and C1424 (LandCruiser RM000000XIG0QJX_01.html).

DTC Code
DTC Detection Condition
Trouble Area
C1422
When the stop light switch is off, the PMC terminal voltage is higher than 0.86 V for 5 seconds or more while the vehicle is being driven at a speed of 3 km/h (2mph) or more.
  1. STOP fuse
  2. Stop light switch assembly
  3. Stop light switch circuit
  4. Master cylinder pressure sensor circuit
  5. Brake actuator assembly (Master cylinder pressure sensor)

WIRING DIAGRAM

Refer to DTC C1425 (LandCruiser RM000000XIE0VHX_02.html).

INSPECTION PROCEDURE

NOTICE:
  1. When replacing the skid control ECU (brake actuator assembly), perform calibration (LandCruiser RM000000XHR0BKX.html).
  2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
When DTC C1425 is output together with DTC C1422, inspect and repair the trouble areas indicated by DTC C1425 first (LandCruiser RM000000XIE0VHX.html).
1.READ VALUE USING INTELLIGENT TESTER (STOP LIGHT SW)

  1. Turn the ignition switch off

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the intelligent tester on.

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

    ABS/VSC/TRC
    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 switch display observed on the intelligent tester changes according to the brake pedal operation.

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


NG
Go to step 4
OK


2.CHECK BRAKE PEDAL AND STOP LIGHT SWITCH ASSEMBLY INSTALLATION

  1. Turn the ignition switch off.

  1. Check the brake pedal height and stop light switch assembly installation (LandCruiser RM000002W8X06QX.html).

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


NG
ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH ASSEMBLY (LandCruiser RM000002W8X06QX.html)
OK


3.RECONFIRM DTC

  1. Clear the DTCs (LandCruiser RM000000XHV0KEX.html).

  1. Start the engine.

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

  1. Check if the same DTC is output (LandCruiser RM000000XHV0KEX.html).

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


B
REPLACE BRAKE ACTUATOR ASSEMBLY (LandCruiser RM0000034UX02TX.html)
A

USE SIMULATION METHOD TO CHECK (LandCruiser RM000003YMJ00XX.html)

4.CHECK TERMINAL VOLTAGE AND RESISTANCE (STOP LIGHT SWITCH ASSEMBLY POWER SOURCE TERMINAL)

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

  1. Disconnect the A85 stop light switch assembly connector.



    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Brake Control Dynamic Control Systems.Anti-Lock Brake System. Dtc C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A85-1(B) - Body ground
    		Always
    		11 to 14 V
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Stop Light Switch Assembly)

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A85-3 (GND) - Body ground
    		Always
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.CHECK TERMINAL VOLTAGE (STP)

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

  1. Disconnect the A6 skid control ECU (brake actuator assembly) connector.



    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Brake Control Dynamic Control Systems.Anti-Lock Brake System. Dtc C1422 Master Cylinder Pressure Sensor Zero Point High Malfunction

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A6-2 (STP) - Body ground
    		Brake pedal depressed
    		8 to 14 V
    Brake pedal released
    		Below 1.5 V
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Skid Control ECU [Brake Actuator Assembly])


NG
Go to step 6
OK

REPLACE BRAKE ACTUATOR ASSEMBLY (LandCruiser RM0000034UX02TX.html)

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

  1. Disconnect the A85 stop light switch assembly connector.

  1. Disconnect the A6 skid control ECU (brake actuator assembly) connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A85-2 (L) - A6-2 (STP)
    		Always
    		Below 1 Ω
    A85-2 (L) or A6-2 (STP) - Body ground
    		Always
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE STOP LIGHT SWITCH ASSEMBLY (LandCruiser RM000003MWQ02KX.html)