DTC C1422: Master Cylinder Pressure Sensor Zero Point High Malfunction [06/2015 - ]: Procedure

1. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [06/2015 - ]

   Chassis > ABS/VSC/TRAC > Clear DTCs 

2. Turn the ignition switch off.
3. Start the engine.
4. Perform a road test.
5. Check for DTCs.

   Refer to DTC CHECK / CLEAR [06/2015 - ]

   Chassis > ABS/VSC/TRAC > Trouble Codes 

   Result

   Result	Proceed to
   DTC C1422 is output.	A
   DTCs C1422 and C1425 are output.	B

Result:  3

B 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS. Refer to  DTC C1425: Open in Stop Light Switch Circuit [06/2015 - ]  

Result:  1

A 

See step  2

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the Techstream on.
4. Select the Data List using the Techstream.

   Refer to DATA LIST / ACTIVE TEST [06/2015 - ]

   Chassis > ABS/VSC/TRAC > Data List 

   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	-

   Chassis > ABS/VSC/TRAC > Data List 

   Tester Display
   Stop Light SW

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

   OK

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

   Result

   Proceed to
   OK
   NG

Result:  2

NG 

See step  5

Result:  1

OK 

See step  3

1. Select the Data List using the Techstream.

   Refer to DATA LIST / ACTIVE TEST [06/2015 - ]

   Chassis > ABS/VSC/TRAC > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Master Cylinder Pressure	Master cylinder pressure sensor pressure	Min.: 0.00 Mpa Max.: 23.28 Mpa	Brake pedal depressed: Proportional to pedal force Brake pedal released: 0.00 to 1.76 Mpa	-

   Chassis > ABS/VSC/TRAC > Data List 

   Tester Display
   Master Cylinder Pressure

   OK

   Data List pressure is within standard range.

   Result

   Proceed to
   OK
   NG

Result:  2

NG 

REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [06/2015 - ] 

Result:  1

OK 

See step  4

1. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [06/2015 - ]

   Chassis > ABS/VSC/TRAC > Clear DTCs 

2. Turn the ignition switch off.
3. Start the engine.
4. Perform a road test.
5. Check if the same DTC is output.

   Refer to DTC CHECK / CLEAR [06/2015 - ]

   Chassis > ABS/VSC/TRAC > Trouble Codes 

   Result

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

Result:  1

A 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [06/2015 - ] 

Result:  2

B 

REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [06/2015 - ] 

1. Turn the ignition switch off.
2. Check the brake pedal height and stop light switch assembly installation.

   Refer to ADJUSTMENT [06/2015 - ]

   OK

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

   Result

   Proceed to
   OK
   NG

Result:  2

NG 

ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH ASSEMBLY. Refer to  ADJUSTMENT [06/2015 - ] 

Result:  1

OK 

See step  6

1. Inspect the stop light switch assembly.

   Refer to INSPECTION [06/2015 - ]

   Result

   Proceed to
   OK
   NG

Result:  2

NG 

REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to  REMOVAL [06/2015 - ] 

Result:  1

OK 

See step  7

1. Turn the ignition switch off.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly))

2. Make sure that there is no looseness at the locking part and the connecting part of the connector.
3. Disconnect the A32 skid control ECU (brake actuator assembly) connector.
4. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A32-35 (STP) - Body ground	Stop light switch assembly on (Brake pedal depressed)	8 to 14 V
   A32-35 (STP) - Body ground	Stop light switch assembly off (Brake pedal released)	Below 1.5 V

   Result

   Proceed to
   OK
   NG

Result:  1

OK 

REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [06/2015 - ] 

Result:  2

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT)