Up to 08/2009

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: C1246/46,C1281/81,C1364/61: Master Cylinder Pressure Sensor Malfunction
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 will be cleared when the master cylinder pressure sensor sends a master cylinder pressure signal or when Test Mode ends. DTC C1281/81 is output only in Test Mode.













WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When replacing the skid control ECU or brake actuator assembly, perform initialization and calibration of the linear solenoid valve Initialization.

PROCEDURE

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

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





Text in Illustration





(b) Disconnect the skid control ECU connectors and the brake actuator 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.

2. INSPECT SKID CONTROL ECU (SENSOR OUTPUT)

(a) Reconnect the skid control ECU connectors and the brake actuator connector.





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

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

Standard Voltage:





(d) Turn the power switch off.

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

Standard Resistance:





Text in Illustration





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

3. READ VALUE USING TECHSTREAM (MASTER CYLINDER PRESSURE SENSOR)

(a) Connect a pedal effort gauge Testing and Inspection.

(b) Connect the Techstream to the DLC3.

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

(d) Select the Data List on the Techstream Data List / Active Test.

ABS/VSC/TRAC





(e) Check the output value of the master cylinder pressure sensor as the brake pedal is depressed.

HINT
* Check the value while electronically controlled brake system control is disabled and without servo assistance.
* The brake warning light / yellow (minor malfunction) is on while electronically controlled brake system control is being disabled.

Standard Voltage:





NG -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal
OK -- Continue to next step.

4. READ VALUE USING TECHSTREAM (WHEEL CYLINDER PRESSURE SENSOR)

(a) Turn the power switch off.

(b) Install a hydro LSPV gauge and bleed air Testing and Inspection.

SST : 09709-29018

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

(d) Select the Data List on the Techstream Data List / Active Test.

ABS/VSC/TRAC





(e) Check the output value of the wheel cylinder pressure sensor at each hydraulic pressure during electronically controlled brake system control.

Standard Voltage:

for Front Wheel Cylinder Pressure Sensor





for Rear Wheel Cylinder Pressure Sensor





NG -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal
OK -- Continue to next step.

5. RECONFIRM DTC

(a) Turn the power switch off.

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

(c) Perform a road test.

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

Result:





B -- REPLACE SKID CONTROL ECU Removal

A -- CHECK FOR INTERMITTENT PROBLEMS How To Proceed With Troubleshooting