Master Reservoir Level Malfunction - Electronically Controlled Brake System
BRAKE CONTROL: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: C1202/68: Master Reservoir Level Malfunction
C1202/68 - Master Reservoir Level Malfunction
DESCRIPTION
When a fluid level drop in the master cylinder reservoir is detected, the signal is input to the skid control ECU.
If the DTC for a fluid level drop is memorized, the warning will be canceled and the DTC will not be stored when the fluid level returns to normal.
WIRING DIAGRAM
INSPECTION PROCEDURE
CAUTION:
When releasing the parking brake, chock the wheels for safety.
NOTICE:
When replacing the skid control ECU, perform initialization and calibration of the linear solenoid valve Initialization.
PROCEDURE
1. CHECK BRAKE FLUID LEVEL
(a) Check that the brake fluid level is sufficient.
OK:
Brake fluid level is sufficient.
HINT
* If the fluid level drops, check for fluid leaks and repair as necessary.
* Check for brake fluid leakage (connection between the brake booster pump, brake master cylinder reservoir and brake actuator, and between the brake actuator and wheel cylinders).
* If no leak exists, add and adjust fluid and then check that the trouble code is not output again.
(b) Check that there are no leaks from the connections between the brake booster pump and brake actuator.
HINT
As a visual check is very difficult, perform the check with the following procedure.
(1) Bleed air from the brake actuator Procedures.
(2) Connect the Techstream to the DLC3.
(3) Turn the ignition switch to ON.
(4) Select the Data List on the Techstream Data List / Active Test.
ABS/VSC/TRAC
(5) Wait for 30 seconds without operating the brake pedal. Then check the accumulator pressure sensor output value's change is within the specified range.
OK:
Accumulator pressure sensor output value's change is within 0.2 V.
NG -- CHECK AND REPAIR BRAKE FLUID LEAKAGE OR ADD FLUID
OK -- Continue to next step.
2. INSPECT BRAKE FLUID LEVEL WARNING SWITCH
(a) Turn the ignition switch off.
(b) Remove the reservoir filler cap and strainer.
(c) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(d) Disconnect the brake fluid level warning switch connector.
(e) Measure the resistance according to the value(s) in the table below.
HINT
A float is located inside the reservoir. Its position changes according to the level of brake fluid.
Standard Resistance:
HINT
If there are no problems after completing the preceding inspection, adjust the brake fluid to the MAX level with the ignition switch ON.
NG -- REPLACE BRAKE MASTER CYLINDER RESERVOIR SUB-ASSEMBLY (BRAKE FLUID LEVEL WARNING SWITCH) Removal
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BRAKE FLUID LEVEL WARNING SWITCH)
(a) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(b) Disconnect the A44 skid control ECU connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. INSPECT SKID CONTROL ECU (SWITCH INPUT)
(a) Reconnect the skid control ECU connector and the brake fluid level warning switch connector.
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Text in Illustration
NG -- REPLACE SKID CONTROL ECU Removal
OK -- Continue to next step.
5. RECONFIRM DTC
(a) Turn the ignition switch off.
(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(c) Turn the ignition switch to ON.
(d) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result:
HINT
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next suspected area Problem Symptoms Table.
B -- REPLACE SKID CONTROL ECU Removal
A -- CHECK FOR INTERMITTENT PROBLEMS How To Proceed With Troubleshooting