C1249

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM: C1249/49: Open in Stop Light Switch Circuit


DESCRIPTION

The skid control ECU inputs the stop light switch signal and detects the brake pedal operation status.

The skid control ECU has an open detection circuit, which outputs this DTC if it detects an open in the stop light input line or 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 booster with master cylinder (skid control ECU), perform initialization and calibration of the linear solenoid valve Initialization.

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 SWITCH (POWER SOURCE TERMINAL)
OK -- Continue to next step.

2. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH)

(a) Connect the Techstream to the DLC3.

(b) Turn the power 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 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 (SKID CONTROL ECU - STOP LIGHT SWITCH)
OK -- Continue to next step.

3. RECONFIRM DTC

(a) Turn the power switch off.

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

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

(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 Problem Symptoms Table, refer back to the table and proceed to the next step Problem Symptoms Table.

B -- REPLACE BRAKE BOOSTER WITH MASTER CYLINDER Removal

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

4. INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL)

(a) Check that the STOP (10 A) fuse is normal.





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

(c) Disconnect the stop light switch 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 (POWER SOURCE CIRCUIT)
OK -- Continue to next step.

5. INSPECT STOP LIGHT SWITCH

(a) 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.

6. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - STOP LIGHT SWITCH)

(a) Make sure that there is no looseness at the locking part and the 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 -- Continue to next step.

7. RECONFIRM DTC

(a) Reconnect the skid control ECU connector and the stop light switch connector.

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

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

(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 Problem Symptoms Table, refer back to the table and proceed to the next step Problem Symptoms Table.

B -- REPLACE BRAKE BOOSTER WITH MASTER CYLINDER Removal

A -- INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT) Exterior Lighting System

8. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - STOP LIGHT SWITCH)

(a) Turn the power 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 and the stop light switch connector.

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

Standard Resistance:





HINT
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Problem Symptoms Table.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE BRAKE BOOSTER WITH MASTER CYLINDER Removal