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 master cylinder solenoid (skid control ECU) inputs stop light switch signals and the condition of brake operation.

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:
- Inspect the fuses for circuits related to this system before performing the following inspection procedure.
- When replacing the master cylinder solenoid, perform calibration Programming and Relearning.

PROCEDURE

1. READ VALUE USING TECHSTREAM (STOP LIGHT SW)

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

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

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / ABS/VSC/TRAC / 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 TERMINAL VOLTAGE (STOP LIGHT SWITCH POWER SOURCE TERMINAL)
OK -- Continue to next step.

2. RECONFIRM DTC

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

(b) Start the engine.

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

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

Result





B -- REPLACE MASTER CYLINDER SOLENOID Disassembly

A -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting

3. CHECK TERMINAL VOLTAGE (STOP LIGHT SWITCH POWER SOURCE TERMINAL)

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

(b) Disconnect the A5 stop light switch connector.

(c) 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 -- Continue to next step.

4. INSPECT STOP LIGHT SWITCH

(a) Remove the stop light switch Removal.

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





Standard Resistance:





Text in Illustration





NG -- REPLACE STOP LIGHT SWITCH Removal
OK -- Continue to next step.

5. CHECK TERMINAL VOLTAGE AND RESISTANCE (+B, GND) C1380

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

6. CHECK TERMINAL VOLTAGE (STP) C1380

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

7. CHECK TERMINAL VOLTAGE (OUT)

(a) Reconnect the A6 stop light control relay connector.

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





Standard Voltage:





Text in Illustration





NG -- REPLACE STOP LIGHT CONTROL RELAY ASSEMBLY Removal
OK -- Continue to next step.

8. CHECK TERMINAL VOLTAGE (STP)

(a) Disconnect the A7 skid control ECU connector.

(b) 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 -- Continue to next step.

9. RECONFIRM DTC

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

(b) Start the engine.

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

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

Result





B -- REPLACE MASTER CYLINDER SOLENOID Disassembly

A -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting