Last Modified: 01-30-2024 6.11:8.1.0 Doc ID: RM100000002GAKU
Model Year Start: 2024 Model: RAV4 Prod Date Range: [10/2023 -           ]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (w/o Vacuum Brake Booster): C120200; Master Reservoir Level Malfunction; 2024 MY RAV4 RAV4 HV [10/2023 -        ]

DTC

C120200

Master Reservoir Level Malfunction

DESCRIPTION

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Note

C120200

Master Reservoir Level Malfunction

Either of the following is detected:

  • The brake fluid level warning switch signal circuit is open for a certain period of time.
  • The reservoir level is low for a certain period of time.
  • Open or short in brake fluid level warning switch (brake booster with master cylinder assembly)
  • Brake fluid leaks
  • Open or short in wire harness
  • Low brake fluid
  • No. 1 skid control ECU (brake booster with master cylinder assembly)

Comes on
  • SAE Code: C1202
  • Output ECU: Both skid control ECUs

HINT:

DTC C120200 is cleared when the conditions return to normal.

C120200 DTC Detection Conditions

 

Vehicle Condition

Pattern 1

Pattern 2

Diagnosis Condition

-

-

-

Malfunction Status

The brake fluid level warning switch signal circuit is open for a certain period of time

○

-

The reservoir level is low for a certain period of time

-

○

Detection Time

-

-

Number of Trips

1 trip

1 trip

HINT:

DTC will be output when conditions for either of the patterns in the table above are met.

MONITOR DESCRIPTION

When the ignition switch is turned to ON and the fluid level warning switch (brake booster with master cylinder assembly) is on for a certain amount of time, the No. 2 skid control ECU (brake actuator assembly) judges that the brake fluid level in the reservoir is low and illuminates the MIL and stores this DTC.

MONITOR STRATEGY

Related DTCs

C1202: Reservoir level too low

Required Sensors/Components(Main)

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

No. 2 skid control ECU (brake actuator assembly)

Required Sensors/Components(Related)

No. 2 skid control ECU (brake actuator assembly)

Frequency of Operation

Continuous

Duration

20 seconds

MIL Operation

Immediately

Sequence of Operation

None

TYPICAL ENABLING CONDITIONS

Monitor runs whenever the following DTCs are not stored

C123B: Brake system voltage input open circuit

U025E: Lost communication with electronic brake booster control unit (C-bus)

Ignition switch

On

TYPICAL MALFUNCTION THRESHOLDS

Either of the following conditions is met

-

Reservoir level switch state

On

Serial communication with IC

Invalid

COMPONENT OPERATING RANGE

All of the following conditions are met

-

Serial communication with IC

Valid

Ignition switch

On

Reservoir level switch state

Off

CONFIRMATION DRIVING PATTERN

NOTICE:

When performing the normal judgment procedure, make sure that the driver door is closed and is not opened at any time during the procedure.

HINT:

  • After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
  • When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
  1. Connect the GTS to the DLC3.
  2. Turn the ignition switch to ON and turn the GTS on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the ignition switch off.
  5. Turn the ignition switch to ON (READY) and turn the GTS on.
  6. Wait 20 seconds. [*]

    HINT:

    [*]: Normal judgment procedure.

    The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

  7. Enter the following menus: Chassis / Brake/EPB / Utility / All Readiness.
  8. Check the DTC judgment result.

    HINT:

    • If the judgment result shows NORMAL, the system is normal.
    • If the judgment result shows ABNORMAL, the system has a malfunction.
    • If the judgment result shows INCOMPLETE, perform driving pattern again.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

After replacing the No. 1 skid control ECU (brake booster with master cylinder assembly), perform "Calibration" after performing "Reset Memory".

Click here 2022 - 2024 MY RAV4 RAV4 HV [12/2021 -        ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (w/o Vacuum Brake Booster): UTILITY

PROCEDURE

1.

CHECK DTC

(a) Check the DTCs that are output.

Chassis > Brake Booster > Trouble Codes

Chassis > Brake/EPB > Trouble Codes

Result

Proceed to

Only DTC C120200 is output.

A

DTCs other than C120200 are output.

B
B

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS
A

2.

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 with accumulator pump assembly, brake fluid level warning switch (brake booster with master cylinder assembly), brake booster with master cylinder assembly, and wheel cylinders).

HINT:

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

Click here 2022 - 2024 MY RAV4 RAV4 HV [12/2021 -        ]; BRAKE SYSTEM (OTHER): BRAKE FLUID (w/o Vacuum Brake Booster): ON-VEHICLE INSPECTION

(2) Check the thickness of the brake pad lining.

for Front Brake: Click here 2019 - 2024 MY RAV4 RAV4 HV [11/2018 -        ]; BRAKE (FRONT): FRONT BRAKE: INSPECTION

for Rear Brake: Click here 2019 - 2024 MY RAV4 RAV4 HV [11/2018 -        ]; BRAKE (REAR): REAR BRAKE: INSPECTION

HINT:

If the thickness is less than the standard, replace the brake pads with new ones.

(b) Check that there are no leaks from the connections between the brake booster with accumulator pump 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 2022 - 2024 MY RAV4 RAV4 HV [12/2021 -        ]; BRAKE SYSTEM (OTHER): BRAKE FLUID (w/o Vacuum Brake Booster): BLEEDING

(2) Turn the ignition switch off.

(3) Disconnect the A103*1 or A110*2 brake pedal stroke sensor assembly connector.

  • *1: except TMC Made
  • *2: for TMC Made

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

(5) 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.

Chassis > Brake Booster > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

ECB Motor Relay

Motor relay operation request

OFF / ON

OFF: Relay off

ON: Relay on

ECB: Electronically Controlled Brake System

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 > Brake Booster > Data List

Tester Display

ECB Motor Relay

Accumulator Pressure

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

3.

INSPECT BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY

(a) Turn the ignition switch off.

*a

Component without harness connected

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

(b) Reconnect the A103*1 or A110*2 brake pedal stroke sensor assembly connector.

  • *1: except TMC Made
  • *2: for TMC Made

(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 A107 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 fluid level warning switch (brake booster with master cylinder assembly). Its position changes according to the level of brake fluid.

Standard Resistance:

Tester Connection

Condition

Specified Condition

1 (+) - 2 (E)

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

1.84 to 2.16 kΩ

1 (+) - 2 (E)

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

Below 1 Ω

(Brake fluid level is low)

(h) If there are no problems after completing the preceding inspection, adjust the brake fluid to the MAX level with the ignition switch turned to ON.

NG

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY
OK

4.

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

(a) Turn the ignition 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 A104 No. 1 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

A104-12 (LBL) - A107-1 (+)

Always

Below 1 Ω

A104-12 (LBL) or A107-1 (+) - Body ground

Always

10 kΩ or higher

A107-2 (E) - Body ground

1 minute or more after disconnecting the cable from the negative (-) auxiliary battery terminal

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

INSPECT BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY (SWITCH INPUT)

(a) Reconnect the A104 No. 1 skid control ECU (brake booster with master cylinder assembly) connector.

*a

Front view of wire harness connector

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

(b) Turn the ignition switch to ON.

(c) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

A107-1 (+) - Body ground

Ignition switch ON

11 to 14 V
NG

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY

OK

6.

CLEAR DTC

(a) Turn the ignition switch off.

(b) Reconnect the A107 brake fluid level warning switch (brake booster with master cylinder assembly) connector.

(c) Clear the DTCs.

Chassis > Brake Booster > Clear DTCs

(d) Turn the ignition switch off.

NEXT

7.

RECONFIRM DTC

(a) Based on the Freeze Frame Data and interview with the customer, attempt to reproduce the conditions when the malfunction occurred.

(b) Check if the same DTC is output.

Chassis > Brake Booster > Trouble Codes

Result

Proceed to

DTC C120200 is not output.

A

DTC C120200 is output.

B
A

USE SIMULATION METHOD TO CHECK

B

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY