DTC C14B6: Stroke Sensor / Reaction Force Pressure Sensor Output Inconsistent [04/2018 - ]: Procedure

1. Interview the customer to check the vehicle conditions when the brake warning light / yellow (minor malfunction) illuminated.
2. Using the Techstream, read the "Shift Lever Position", "Vehicle Speed", "Yaw Rate Sensor", "Steering Angle Sensor", "Stop Light SW", "Stroke Sensor", "Reaction Force Pressure", "Servo Pressure" and "Accumulator Pressure" of the Freeze Frame Data stored when the DTC was stored.

   HINT: 

   • Freeze Frame Data is only stored once when a DTC is stored.
   • If other DTCs are output, repair any malfunctions related to those DTCs first, and then reproduce the conditions that caused DTC C14B6 to be stored based on the interview with the customer.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  2

1. Turn the power switch off.
2. Mount a pedal effort gauge.
3. Disconnect the A40 brake booster pump assembly connector.
4. Depress the brake pedal 10 times or more until it becomes hard.

   HINT: 

   Depressing the brake pedal with the connector of the brake booster pump assembly disconnected drops the accumulator pressure to approximately 0 MPa.

5. Connect an LSPV gauge set.
6. Select the Data List on the Techstream.

   Refer to DATA LIST / ACTIVE TEST [04/2018 - ]

   Chassis > ABS/VSC/TRAC > Data List 

   Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
   Stroke Sensor	Brake pedal stroke sensor	Min.: 0.00 V, Max.: 5.00 V	Brake pedal released: 0.65 to 1.35 V	Reading increases when brake pedal is depressed

   Chassis > ABS/VSC/TRAC > Data List 

   Tester Display
   Stroke Sensor

7. Slowly depress the brake pedal and check the brake pedal stroke sensor assembly output voltages and the wheel cylinder pressure with respect to brake pedal depression force.
   NOTE:

   Check the wheel cylinder pressure with the switching solenoid (SSA, SGH) off and an accumulator pressure of 0 MPa.

   Standard Pressure

   FOR FRONT RIGHT WHEEL
   
   

   Brake Effort [N (kgf, lbf)]	Stroke Sensor [V]	Hydraulic Pressure [MPa (kgf/cm2 , psi)]
   200 (20, 45.0)	1.52 to 2.22	0.04 (0.4, 5.8) to 2.04 (20.8, 296)
   500 (51, 112.4)	1.81 to 2.51	2.06 (21.0, 299) to 4.06 (41.4, 589)

   FOR FRONT LEFT WHEEL
   
   

   Brake Effort [N (kgf, lbf)]	Stroke Sensor [V]	Hydraulic Pressure [MPa (kgf/cm2 , psi)]
   200 (20, 45.0)	1.52 to 2.22	0.04 (0.4, 5.8) to 2.04 (20.8, 296)
   500 (51, 112.4)	1.81 to 2.51	2.06 (21.0, 299) to 4.06 (41.4, 589)

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to  REMOVAL [04/2018 - 08/2021]  , or refer to  REMOVAL [08/2021 - ] 

Result: 

NG 

See step  3

1. Turn the power switch off.
2. Reconnect the A40 brake booster pump assembly connector.
3. Replace brake pedal stroke sensor assembly.

   Refer to REMOVAL [04/2018 - 08/2021] , or refer to REMOVAL [08/2021 - ]

4. Perform zero point calibration of the brake pedal stroke sensor assembly.

   Refer to INITIALIZATION [04/2018 - 08/2021] , or refer to INITIALIZATION [08/2021 - ]

   Chassis > ABS/VSC/TRAC > Utility 

   Tester Display
   ECB Utility

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  4

1. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [04/2018 - ]

   Chassis > ABS/VSC/TRAC > Clear DTCs 

2. Perform a road test under the same malfunction conditions recreated based on the Freeze Frame Data or customer problem analysis.
3. Turn the power switch off and wait for 2 minutes or more.
4. Turn the power switch on (IG).
5. Check if the same DTC is output.

   Refer to DTC CHECK / CLEAR [04/2018 - ]

   Chassis > ABS/VSC/TRAC > Trouble Codes 

   Result

   Result	Proceed to
   DTC C14B6 is not output.	A
   DTC C14B6 is output.	B

Result: 

A 

END 

Result: 

B 

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to  REMOVAL [04/2018 - 08/2021]  , or refer to  REMOVAL [08/2021 - ]