Open in Stop Light Switch Circuit - ABS (Antilock Brake System)

BRAKE CONTROL: ANTI-LOCK BRAKE SYSTEM: C1249/49: Open in Stop Light Switch Circuit
C1249/49 - Open in Stop Light Switch Circuit

DESCRIPTION

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





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
* Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1. CHECK STOP LIGHT SWITCH OPERATION

(a) Check that the stop lights come on when the brake pedal is depressed and go off when the brake pedal is released.





HINT
Check the stop light bulb as it may have burnt out.

NG -- INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL)
OK -- Continue to next step.

2. INSPECT SKID CONTROL ECU TERMINAL VOLTAGE (STP TERMINAL)

(a) Disconnect the 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.

3. INSPECT SKID CONTROL ECU (IG TERMINAL)

(a) Disconnect the skid control ECU connector.

(b) Turn the ignition switch to ON.

(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 (IG CIRCUIT)
OK -- Continue to next step.

4. INSPECT SKID CONTROL ECU (GND TERMINAL)

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





Standard Resistance:





Text in Illustration





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)
OK -- Continue to next step.

5. RECONFIRM DTC

(a) Clear the DTCs ABS (Antilock Brake System).

(b) Check if the same DTCs are recorded.

Result





B -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)

A -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

6. INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL)

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

7. INSPECT STOP LIGHT SWITCH ASSEMBLY

(a) Disconnect the stop light switch connector.





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

Standard Resistance:





Text in Illustration





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

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

(a) Disconnect the skid control ECU connector.

(b) Disconnect the stop light switch 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.

9. RECONFIRM DTC

(a) Clear the DTCs ABS (Antilock Brake System).

(b) Start the engine.

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

(d) Check if the same DTCs are recorded ABS (Antilock Brake System).

Result





B -- INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT)

A -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal