C1246

BRAKE CONTROL: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: C1246/46: Master Cylinder Pressure Sensor Malfunction

DTC C1246/46 - Master Cylinder Pressure Sensor Malfunction

DTC C1281/81 - Master Cylinder Pressure Sensor Output Malfunction (Test Mode DTC)

DTC C1364/61 - Wheel Cylinder Pressure Sensor Malfunction

DESCRIPTION

The master cylinder pressure sensor and the wheel cylinder pressure sensor are built into the brake actuator, and measure the master cylinder pressure and the wheel cylinder pressure sent to the skid control ECU.
DTC C1281/81 can be detected when the master cylinder pressure sensor sends a master cylinder pressure signal or Test Mode ends. DTC C1281/81 is output only in Test Mode.













WIRING DIAGRAM





INSPECTION PROCEDURE

NOTE: When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration.

PROCEDURE

1. CHECK WIRE HARNESS (SKID CONTROL ECU - BRAKE ACTUATOR)





(a) Disconnect the S7 and S10 ECU connectors.
(b) Disconnect the A2 actuator connector.
(c) Measure the resistance of the wire harness side connectors.
Standard resistance:





NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.
2. CHECK SKID CONTROL ECU





(a) Measure the voltage of the connectors.

HINT: Measure the voltage from behind the connector with the connector connected to the skid control ECU.

Standard voltage:





(b) Measure the resistance of the connectors.
Standard resistance:





NG -- REPLACE SKID CONTROL ECU
OK -- Continue to next step.
3. READ VALUE OF TECHSTREAM (MASTER CYLINDER PRESSURE SENSOR)
(a) Check the Data List for proper functioning of the master cylinder pressure sensor.

ABS / VSC / TRAC:





OK:
When the pedal is depressed, displayed voltage on Techstream increase.
NG -- REPLACE BRAKE ACTUATOR ASSEMBLY
OK -- Continue to next step.
4. READ VALUE OF TECHSTREAM (WHEEL CYLINDER PRESSURE SENSOR)
(a) Connect the pedal effort gauge.
(b) Install the LSPV gauge (SST) and bleed air.
SST: 09709-29018
(c) Select the Data List mode on Techstream.

ABS / VSC / TRAC:





(d) Check the output value of the wheel cylinder pressure sensor at each fluid pressure during the Electronically Controlled Brake control.
Standard voltage:
Front wheel cylinder pressure sensor






Rear wheel cylinder pressure sensor






NG -- REPLACE BRAKE ACTUATOR ASSEMBLY
OK -- REPLACE SKID CONTROL ECU