C1202

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 brake fluid reservoir is detected, the signal is input to the skid control ECU.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When replacing the skid control ECU, perform the following operations:

- Initialization of linear solenoid valve and calibration Initialization
- Yaw rate and acceleration sensor zero point calibration Calibration

PROCEDURE

1. CHECK BRAKE FLUID LEVEL IN RESERVOIR

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





OK:

Brake fluid level is proper.

HINT
- If the fluid level drops, check for a fluid leak, and repair if found.
- Check that the brake fluid leakage (Connection between accumulator and actuator, or actuator and wheel cylinder)
- 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 connection between the accumulator pump and actuator.





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

(1) Bleed air from the brake actuator Service and Repair.

(2) Using the Techstream, check the data monitor of the accumulator pressure sensor.

ABS/VSC/TRAC:





(3) 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 AND ADD FLUID
OK -- Continue to next step.

2. INSPECT BRAKE FLUID LEVEL WARNING SWITCH

(a) Disconnect the A18 switch connector.





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

HINT
A float is placed inside the reservoir. Its position can be changed by increasing/decreasing the level of brake fluid.

Standard resistance:





HINT
If there is no problem after finishing the above check, adjust the brake fluid level to the MAX level.

NG -- REPLACE BRAKE FLUID RESERVOIR Removal
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU AND BODY GROUND - BRAKE FLUID LEVEL WARNING SWITCH)

(a) Disconnect the A19 ECU connector.

(b) Disconnect the A18 switch connector.

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

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

4. CHECK SKID CONTROL ECU (SWITCH INPUT VOLTAGE)

(a) Reconnect the A19 ECU connector.





(b) Disconnect the A18 switch connector.

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

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

Standard voltage:





NG -- REPLACE SKID CONTROL ECU Removal
OK -- Continue to next step.

5. RECONFIRM DTC

(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(b) Turn the power switch ON (IG).

(c) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.

HINT
Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.

Result





HINT
If troubleshooting has been carried out according to the "PROBLEM SYMPTOMS TABLE", refer back to the table and proceed to the next step Problem Symptoms Table.

B -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting

A -- REPLACE SKID CONTROL ECU Removal