DTC C1422: Master Cylinder Pressure Sensor Zero Point High Malfunction; DTC C1456: Control Pressure Sensor Zero Point High [08/2019 - ]: Procedure

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

Result: 

NG 

INSPECT STOP LIGHT CIRCUIT 

(Refer to PROBLEM SYMPTOMS TABLE [08/2019 - 08/2020] , or refer to PROBLEM SYMPTOMS TABLE [08/2020 - 08/2022] , or refer to PROBLEM SYMPTOMS TABLE [08/2022 - ] )

Result: 

OK 

See step  2

1. Turn the ignition switch off.
2. Connect the Techstream to the DLC3.
3. Turn the ignition switch to ON.
4. Turn the Techstream on.
5. Enter the following menus: Chassis / ABS/VSC/TRAC / Data List.
   ABS/VSC/TRAC
   
   

   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	-

6. Check that the stop light condition observed on the Techstream changes according to brake pedal operation.

   OK

   The Techstream displays ON or OFF according to brake pedal operation.

Result: 

NG 

See step  5

Result: 

OK 

See step  3

1. Turn the ignition switch off.
2. Check the brake pedal height and stop light switch assembly installation (Refer to ADJUSTMENT [08/2019 - ] ).

   OK

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

Result: 

NG 

ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH 

(Refer to ADJUSTMENT [08/2019 - ] )

Result: 

OK 

See step  4

1. Clear the DTCs (Refer to DTC CHECK / CLEAR [08/2019 - ] ).
2. Start the engine.
3. 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).
4. Check if the same DTC is output (Refer to DTC CHECK / CLEAR [08/2019 - ] ).
   RESULT
   
   

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

Result: 

A 

USE SIMULATION METHOD TO CHECK 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2019 - ] )

Result: 

B 

REPLACE MASTER CYLINDER SOLENOID 

(Refer to DISASSEMBLY [08/2015 - ] )

See step  5

Result: 

OK 

REPLACE MASTER CYLINDER SOLENOID 

(Refer to DISASSEMBLY [08/2015 - ] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR