C1425

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1425: Open in Stop Light Switch Circuit
C1425 - Open in Stop Light Switch Circuit

DESCRIPTION

The skid control ECU detects the brake operating conditions through a signal transmitted by the stop light switch.

The skid control ECU has an open detection circuit, which outputs this DTC when detecting an open in the stop light input line or the ground line of the stop light circuit with the stop light switch off (brake pedal not depressed).





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* When replacing the brake actuator assembly, perform zero point calibration Programming and Relearning.
* Inspect the fuses for circuits related to this system before performing the following inspection procedure.

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)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Chassis / ABS/VSC/TRAC / Data List.

(e) According to the display on the Techstream, read the Data List.

ABS/VSC/TRAC





(f) Check that the stop light switch display observed on the Techstream changes according to brake pedal operation.

OK:

The Techstream displays ON or OFF according to brake pedal operation.

NG -- CHECK HARNESS AND CONNECTOR (STP TERMINAL)
OK -- Continue to next step.

3. RECONFIRM DTC

(a) Turn the ignition switch off.

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

(c) Start the engine.

(d) Depress the brake pedal several times to test the stop light circuit.

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

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 -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

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

4. CHECK HARNESS AND CONNECTOR (STP TERMINAL)

(a) Turn the ignition switch off.





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

(c) Disconnect the skid control ECU connector.

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

Standard Voltage:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal