C1281

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1281: Master Cylinder Pressure Sensor Output Malfunction (Test Mode DTC)

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

DESCRIPTION

DTC C1281 will be cleared when the master cylinder pressure sensor sends a master cylinder pressure signal or when Test Mode ends. DTC C1281 is output only in Test Mode.






WIRING DIAGRAM












INSPECTION PROCEDURE
NOTE:
When replacing the brake actuator assembly, perform zero point calibration and store system information Programming and Relearning.

PROCEDURE

1. CHECK STOP LIGHT OPERATION
(a) Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.
OK:






NG -- INSPECT STOP LIGHT CIRCUIT
OK -- Continue to next step.
2. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH AND BRAKE PEDAL LOAD SENSING SWITCH)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Select the Data List on the Techstream Data List / Active Test.

ABS/VSC/TRAC





(d) Check that the stop light switch display and brake pedal load sensing switch display observed on the Techstream change according to brake pedal operation.
OK:
The Techstream displays ON or OFF according to brake pedal operation.
(e) Slowly depress the brake pedal, and check when the stop light switch and brake pedal load sensing switch turn ON.
OK:
First the stop light switch should turn ON, and then the brake pedal load sensing switch should turn ON.
Result:






D -- CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION
C -- INSPECT SKID CONTROL ECU (FSW+ TERMINAL)
B -- INSPECT SKID CONTROL ECU (STP1 TERMINAL)
A -- Continue to next step.
3. READ VALUE USING TECHSTREAM (MASTER CYLINDER PRESSURE SENSOR)
(a) Select the Data List on the Techstream Data List / Active Test.

ABS/VSC/TRAC





(b) Check that the brake fluid pressure value of the master cylinder pressure sensor observed on the Techstream changes when the brake pedal is depressed.
OK:
When the pedal is depressed, voltage displayed on the Techstream increases.
NG -- REPLACE BRAKE ACTUATOR ASSEMBLY
OK -- Continue to next step.
4. PERFORM TEST MODE (SIGNAL CHECK)
(a) Turn the engine switch off.
(b) Perform the sensor check in the Test Mode procedure Test Mode Procedure.
OK:
All Test Mode DTCs are cleared.
NG -- REPLACE BRAKE ACTUATOR ASSEMBLY
OK -- CHECK FOR INTERMITTENT PROBLEMS
5. INSPECT SKID CONTROL ECU (STP1 TERMINAL)




(a) Turn the engine switch off.
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(c) Disconnect the skid control ECU connector.
(d) Measure the voltage according to the value(s) in the table below.
Standard Voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STP1 CIRCUIT)
OK -- REPLACE BRAKE ACTUATOR ASSEMBLY
6. INSPECT SKID CONTROL ECU (FSW+ TERMINAL)




(a) Turn the engine switch off.
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(c) Disconnect the skid control ECU connector.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (FSW+ CIRCUIT)
OK -- REPLACE BRAKE ACTUATOR ASSEMBLY
7. CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION
(a) Turn the engine switch off.
(b) Check the brake pedal height and stop light switch installation Adjustments.
OK:
The brake pedal height and stop light switch installation are normal.
NG -- ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH
OK -- REPLACE BRAKE PEDAL SUPPORT ASSEMBLY (BRAKE PEDAL LOAD SENSING SWITCH)