Last Modified: 11-20-2023 6.11:8.1.0 Doc ID: RM1000000014VMR
Model Year Start: 2018 Model: Camry HV Prod Date Range: [07/2017 - 09/2018]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: C120F; Open in Master Reservoir Level Switch Circuit; 2018 MY Camry HV [07/2017 - 09/2018]

DTC

C120F

Open in Master Reservoir Level Switch Circuit

DESCRIPTION

If the skid control ECU (brake booster with master cylinder assembly) detects that the brake fluid level is low or there is an open in the brake fluid level warning switch signal circuit, DTC C120F is stored.

DTC No.

Detection Item

INF Code

DTC Detection Condition

Trouble Area

Note

C120F

Open in Master Reservoir Level Switch Circuit

371

The brake fluid level warning switch (brake booster with master cylinder assembly) circuit is open for 2 seconds or more.

  • Open in brake fluid level warning switch (brake booster with master cylinder assembly)
  • Open in wire harness
  • Skid control ECU (brake booster with master cylinder assembly)

Electronically controlled brake system DTC

WIRING DIAGRAM

Refer to DTC C1202.

Click here 2018 MY Camry HV [07/2017 - 09/2018]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: C1202; Master Reservoir Level Malfunction

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 2018 MY Camry HV [07/2017 - 09/2018]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: INITIALIZATION

PROCEDURE

1.

CHECK BRAKE FLUID LEVEL

(a) Check that the brake fluid level is sufficient.

HINT:

If the fluid level is low, check for fluid leaks, and repair as necessary.

(1) Check for brake fluid leaks (connection between the brake booster pump assembly, brake actuator assembly, brake booster with master cylinder assembly and wheel cylinders).

HINT:

If no leaks exist, add and adjust fluid using the Techstream.

Click here 2018 MY Camry HV [07/2017 - 09/2018]; BRAKE SYSTEM (OTHER): BRAKE FLUID: ON-VEHICLE INSPECTION

(b) Check that there are no leaks from the connections between the brake booster pump assembly, brake actuator assembly and brake booster with master cylinder assembly.

HINT:

As a visual check is very difficult, perform the check with the following procedure.

(1) Bleed the air from the brake system.

Click here 2018 MY Camry HV [07/2017 - 09/2018]; BRAKE SYSTEM (OTHER): BRAKE FLUID: BLEEDING

(2) Turn the power switch off.

(3) Disconnect the A39 brake pedal stroke sensor assembly connector.

(4) Select the Data List on the Techstream.

Chassis > ABS/VSC/TRAC > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

MT Voltage Value

MT voltage value

Min.: 0.00 V, Max.: 20.00 V

Pump motor off: 0.00 V

Pump motor on: 12.00 V

-

Accumulator Pressure

Accumulator pressure output value

Min.: 0.00 MPa, Max.: 24.48 MPa

15.00 to 21.00 MPa

(Pressure stable and pump motor stopped)

When brake fluid is stored in the accumulator: Accumulator pressure changes in accordance with volume of fluid stored in the accumulator

Chassis > ABS/VSC/TRAC > Data List

Tester Display

MT Voltage Value

Accumulator Pressure

(5) Depress the brake pedal several times to operate the pump motor, then wait until it stops.

(6) After the pump motor stops, wait for 30 seconds, then check the drop in the accumulator pressure sensor output value and the state of the pump motor.

Result

Proceed to

The drop in the accumulator pressure sensor output value is less than 2.50 MPa 30 seconds after the pump motor stops, and the pump motor does not operate within 30 seconds after the pump motor stops.

A

The drop in the accumulator pressure sensor output value is 2.50 MPa or more 30 seconds after the pump motor stops, or the pump motor operates within 30 seconds after the pump motor stops.

B

B

CHECK AND REPAIR BRAKE FLUID LEAKS OR ADD FLUID

A

2.

INSPECT BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (BRAKE FLUID LEVEL WARNING SWITCH)

(a) Turn the power switch off.

*a

Component without harness connected

(Brake Fluid Level Warning Switch (Brake Booster with Master Cylinder Assembly))

(b) Reconnect the A39 brake pedal stroke sensor assembly connector.

(c) Remove the brake master cylinder reservoir filler cap assembly.

(d) Make sure that there is no looseness at the locking part and the connecting part of the connector.

OK:

The connector is securely connected.

(e) Disconnect the A1 brake fluid level warning switch (brake booster with master cylinder assembly) connector.

(f) Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.

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

HINT:

A float is located inside the brake master cylinder reservoir assembly (brake booster with master cylinder assembly). Its position changes according to the level of brake fluid.

Standard Resistance:

Tester Connection

Condition

Specified Condition

2 (LBL) - 1 (GND)

Brake fluid level warning switch (brake booster with master cylinder assembly) off (float up)

1.84 to 2.16 kΩ

2 (LBL) - 1 (GND)

Brake fluid level warning switch (brake booster with master cylinder assembly) on (float down)

Below 1 Ω

(Brake fluid level is low)

HINT:

If there are no problems after completing the preceding inspection, adjust the brake fluid to the MAX level with the power switch on (IG).

NG

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY

OK

3.

CHECK HARNESS AND CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY - BRAKE FLUID LEVEL WARNING SWITCH (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY))

(a) Turn the power switch off.

(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.

OK:

The connector is securely connected.

(c) Disconnect the A40 skid control ECU (brake booster with master cylinder assembly) connector.

(d) Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

A40-16 (LBL) - A1-2 (LBL)

Always

Below 1 Ω

A40-16 (LBL) or A1-2 (LBL) - Body ground

Always

10 kΩ or higher

A1-1 (GND) - Body ground

Always

Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

4.

CHECK BRAKE DISC

(a) Reconnect the A40 skid control ECU (brake booster with master cylinder assembly) connector.

(b) Reconnect the A1 brake fluid level warning switch (brake booster with master cylinder assembly) connector.

(c) Disconnect the A39 brake pedal stroke sensor assembly connector.

(d) Perform a road test according to Freeze Frame Data or customer problem analysis. While driving, check for abnormal brake pedal vibration caused by brake discs that are worn or have excess runout.

OK:

Brake pedal does not vibrate during braking.

HINT:

  • An unevenly worn disc may vibrate the caliper pistons and cause fluctuations in brake line pressure, triggering a malfunction detection condition.
  • The brake pedal does not kick back due to caliper piston vibration during electronically controlled brake system control.
  • If the brake pedal stroke sensor assembly connector is disconnected, the fail-safe function will prohibit electronically controlled brake system control.
  • The Active Test does not prohibit electronically controlled brake system control when the vehicle is being driven, so disconnect the brake pedal stroke sensor assembly connector before continuing with inspection.
  • Uneven disc wear can be checked by measuring the disc thickness variation.

    for Front Brake: Click here 2018 - 2024 MY Camry HV [07/2017 -        ]; BRAKE (FRONT): FRONT BRAKE: INSPECTION

    for Rear Brake: Click here 2018 - 2024 MY Camry HV [07/2017 -        ]; BRAKE (REAR): REAR BRAKE: INSPECTION

NG

REPLACE BRAKE DISC

OK

5.

RECONFIRM DTC

(a) Turn the power switch off.

(b) Reconnect the A39 brake pedal stroke sensor assembly connector.

(c) Clear the DTCs.

Chassis > ABS/VSC/TRAC > Clear DTCs

(d) Turn the power switch off.

(e) Turn the power switch on (READY).

(f) Perform a road test.

(g) Check if the same DTC is output.

Chassis > ABS/VSC/TRAC > Trouble Codes

Result

Proceed to

DTC C120F is not output.

A

DTC C120F is output.

B

A

USE SIMULATION METHOD TO CHECK

B

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY