C1431

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1430,C1431: Brake Pedal Load Sensing Switch OFF Stuck Malfunction
C1431 - Brake Pedal Load Sensing Switch ON Stuck Malfunction

DESCRIPTION

The brake pedal load sensing switch operates when the brake pedal is depressed with force exceeding a predetermined level.

The skid control ECU detects if the brake pedal is depressed or not via this circuit.





WIRING DIAGRAM

Refer to DTC C1429 C1429.

INSPECTION PROCEDURE

NOTICE:
When replacing the brake actuator assembly, perform zero point calibration Component Tests and General Diagnostics.

HINT
When C1425 is output together with C1430 and/or C1431, inspect and repair the trouble areas indicated by C1425 first C1425.

PROCEDURE

1. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH/BRAKE PEDAL LOAD SENSING SWITCH)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Select the Data List mode 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:





C -- CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION

B -- INSPECT BRAKE PEDAL LOAD SENSING SWITCH
A -- Continue to next step.

2. RECONFIRM DTC

(a) Turn the ignition switch off.

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

(c) Start the engine.

(d) Perform the road and braking test.

(e) Check if the same DTC is output Reading and Clearing Diagnostic Trouble Codes.

Result:





B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) How To Proceed With Troubleshooting

3. INSPECT BRAKE PEDAL LOAD SENSING SWITCH





NOTICE:
* Do not remove the brake pedal load sensing switch from the brake pedal support assembly.
* When there is a malfunction in the brake pedal load sensing switch, replace the brake pedal support assembly.

(a) Turn the ignition switch off.

(b) Make sure that there is no looseness in the locking part and connecting part of the connector.

(c) Disconnect the brake pedal load sensing switch connector.

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

Standard Resistance:





NG -- REPLACE BRAKE PEDAL SUPPORT ASSEMBLY (BRAKE PEDAL LOAD SENSING SWITCH) Removal
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BRAKE PEDAL LOAD SENSING SWITCH)

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





(b) Disconnect the skid control ECU connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

5. CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION

(a) Turn the ignition 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 Adjustments

OK -- REPLACE BRAKE PEDAL SUPPORT ASSEMBLY (BRAKE PEDAL LOAD SENSING SWITCH) Removal