Toyota Avalon Service & Repair Manual: Reaction Force Pressure Sensor Zero Point Malfunction (C14B3)

DESCRIPTION

The reaction force pressure sensor detects and outputs the brake fluid pressure of the stroke simulator, which changes in accordance with brake pedal operation, to the skid control ECU (brake booster with master cylinder assembly).

DTC No.

Detection Item

INF Code

DTC Detection Condition

Trouble Area

MIL

Note

C14B3

Reaction Force Pressure Sensor Zero Point Malfunction

204

When the brake pedal is not depressed, the reaction force pressure sensor output value is -0.63 MPa (-6.4 kgf/cm2, -91.4 psi) or less or 1.53 MPa (15.6 kgf/cm2, 222 psi) or more for 3 seconds or more.

Skid control ECU (brake booster with master cylinder assembly)

Comes on

  • INF Code 204: SAE Code C14B3
  • Electronically controlled brake system DTC

MONITOR DESCRIPTION

When the brake pedal is not operated and the value of the reaction force pressure sensor exceeds a specific value, or the value is less than a specific value for a certain amount of time, the skid control ECU (brake booster with master cylinder assembly) judges that the zero point of the reaction force pressure sensor is abnormal and illuminates the MIL and stores this DTC.

MONITOR STRATEGY

Related DTCs

C14B3: Reaction force pressure sensor exceeded learning limit

Required Sensors/Components(Main)

Brake actuator (brake booster with master cylinder assembly)

Required Sensors/Components(Related)

Brake pedal stroke sensor assembly

Brake actuator (brake booster with master cylinder assembly)

Stop light switch assembly

Frequency of Operation

Continuous

Duration

3 seconds

MIL Operation

Immediately

Sequence of Operation

None

TYPICAL ENABLING CONDITIONS

Monitor runs whenever the following DTCs are not stored

C0562 (Brake pedal stroke sensor assembly voltage circuit/open)

C124B (Brake pedal stroke sensor assembly invalid data)

C14B0 (Reaction force pressure sensor voltage circuit check)

C14B1 (Reaction force pressure sensor lost communication)

C14B2 (Reaction force pressure sensor internal malfunction)

C14B4 (Reaction force pressure sensor intermittent/erratic)

C14B5 (Reaction force pressure sensor invalid data)

P057C, P05DD (Brake pedal stroke sensor assembly open circuit)

P057D, P05DE (Brake pedal stroke sensor assembly circuit high)

P057E, P05DF (Brake pedal stroke sensor assembly intermittent/erratic)

P05E0 (Brake pedal stroke sensor assembly "1"/"2" correlation)

All of the following conditions are met

-

Brake pedal stroke sensor assembly circuit fail

Not detected

Reaction force pressure sensor circuit fail

Not detected

Brake

Off

TYPICAL MALFUNCTION THRESHOLDS

Reaction force pressure sensor

Less than -0.63 MPa (-6.4 kgf/cm2, -91.4 psi), or higher than 1.53 MPa (15.6 kgf/cm2, 222 psi)

COMPONENT OPERATING RANGE

All of the following conditions are met

-

Brake pedal stroke sensor assembly circuit fail

Not detected

Reaction force pressure sensor circuit fail

Not detected

Brake

Off

Reaction force pressure sensor

-0.63 MPa (-6.4 kgf/cm2, -91.4 psi) or more, and 1.53 MPa (15.6 kgf/cm2, 222 psi) or less

CONFIRMATION DRIVING PATTERN

  1. Connect the Techstream to the DLC3.
  2. Turn the power switch on (IG).
  3. Turn the Techstream on.
  4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  5. Turn the power switch off.
  6. Turn the power switch on (IG).
  7. Turn the Techstream on.
  8. Wait 3 seconds.
  9. Enter the following menus: Chassis / ABS/VSC/TRAC / Trouble Codes.
  10. Read the DTCs.

    HINT:

    • If a DTC is output, the system is malfunctioning.
    • If a DTC is not output, perform the following procedure.
  11. If the DTCs are not output, perform a universal trip and check for permanent DTCs.

    Click here

    HINT:

    • If a permanent DTC is output, the system is malfunctioning.
    • If no permanent DTCs are output, the system is normal.

CAUTION / NOTICE / HINT

NOTICE:

After replacing the skid control ECU (brake booster with master cylinder assembly), perform linear solenoid valve offset learning, ABS holding solenoid valve learning, yaw rate and acceleration sensor zero point calibration and system information memorization after performing "Reset Memory".

Click here

PROCEDURE

1.

CHECK BRAKE PEDAL

(a) Check that the brake pedal and the brake pedal stroke sensor assembly are properly installed and that the pedal can be depressed normally.

(b) Check and adjust the brake pedal height.

Click here

(c) Adjust the brake pedal stroke sensor assembly.

Click here

NEXT

2.

READ VALUE USING TECHSTREAM (REACTION FORCE PRESSURE)

(a) Select the Data List on the Techstream.

Click here

Chassis > ABS/VSC/TRAC > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Reaction Force Pressure

Pressure value of stroke simulator

Min.: 0.00 MPa, Max.: 24.48 MPa

Brake pedal released: 0.00 MPa

Brake pedal is being depressed: Changes in proportion to the depression force of the brake pedal

Chassis > ABS/VSC/TRAC > Data List

Tester Display

Reaction Force Pressure

(b) Check that the reaction force pressure sensor output value is within 0.00 to 1.53 MPa when the brake pedal is not depressed.

OK:

The reaction force pressure sensor output value is within 0.00 to 1.53 MPa.

HINT:

If the reaction force pressure sensor output value is within 0.00 to 1.53 MPa, the skid control ECU (brake booster with master cylinder assembly) automatically performs zero point calibration every time the power switch is turned on (IG).

Therefore, if the reaction force pressure sensor output value is not within 0.00 to 1.53 MPa, replace the skid control ECU (brake booster with master cylinder assembly) with a new one.

NG

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY

OK

3.

RECONFIRM DTC

(a) Clear the DTCs.

Click here

Chassis > ABS/VSC/TRAC > Clear DTCs

(b) Turn the power switch off.

(c) Turn the power switch on (IG).

(d) Check if the same DTC is output.

Click here

Chassis > ABS/VSC/TRAC > Trouble Codes

HINT:

Even if the DTC is cleared, it will immediately be output again if the reaction force pressure sensor zero point malfunction remains.

Result

Proceed to

DTC C14B3 is not output.

A

DTC C14B3 is output.

B

A

USE SIMULATION METHOD TO CHECK

B

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY

    EPB System Malfunction (C13AF)

    Servo Pressure Sensor Zero Point Malfunction (C14C3)

    See More:

    Toyota Avalon Service & Repair Manual > Front Power Seat Control System(for Gasoline Model With Memory): Short in Sensor with Motor Power Supply Circuit (B2658)
    DESCRIPTION This DTC is stored when a power seat motor operates (a position control sensor is being supplied with power) and the power supply voltage does not rise to the specified value. DTC No. Detection Item DTC Detection Condition Trouble Area B2658 Short in Sensor with Motor Power Supply Circui ...

    Toyota Avalon Owners Manual

    Toyota Avalon Service & Repair Manual

    © 2020 Copyright www.tavalon.net
    0.0291