C1249

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1249/49: Open in Stop Light Switch Circuit

DTC C1249/49 - Open in Stop Light Switch Circuit

DESCRIPTION

The skid control ECU (housed in the ABS & TRACTION actuator assembly) inputs the stop light switch signal 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 while the stop light switch is OFF.





WIRING DIAGRAM









INSPECTION PROCEDURE

NOTE: When replacing the ABS & TRACTION actuator assembly, perform zero point calibration Programming and Relearning.

HINT: After steps 1, 2 and 3 are completed, start the inspection from step 4 when using Techstream and start from step 5 when not using Techstream.

PROCEDURE

1. CHECK STOP LIGHT SWITCH OPERATION
(a) Check that the stop light comes on when the brake pedal is depressed, and goes off when the brake pedal is released.
OK:
Stop light switch function is normal.

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

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

2. INSPECT SKID CONTROL ECU (STP1 TERMINAL VOLTAGE)
(a) Disconnect the skid control ECU connector.





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





Result:





C -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STP1 CIRCUIT)
B -- RECONFIRM DTC
A -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (STP1 TO STP2 CIRCUIT)





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






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STP1 TO STP2 CIRCUIT)
OK -- Continue to next step.

4. PERFORM ACTIVE TEST USING TECHSTREAM (STOP LIGHT RELAY)
(a) Reconnect the skid control ECU connector.
(b) Connect Techstream to the DLC3.
(c) Turn the ignition switch on (IG) and turn Techstream main switch on.
(d) Select "ACTIVE TEST" on Techstream.

ACTIVE LIST: ABS / VSC / TRAC





(e) Check that "ON" and "OFF" of the stop light can be shown on the rear combination light by Techstream.
OK:
The stop light turns on or off in accordance with Techstream.

HINT: Reinstall the sensors, connectors, etc. and restore the vehicle to its prior conditions before rechecking for DTCs.

OK -- RECONFIRM DTC

NG -- Continue to next step.

5. INSPECT ENGINE ROOM R/B (BRK RELAY POWER SOURCE TERMINAL VOLTAGE)





(a) Remove the BRK relay.
(b) Turn the ignition switch on (IG).
(c) Measure the voltage according to the value(s) in the table below.
Voltage:






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

6. INSPECT BRK RELAY





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






NG -- REPLACE BRK RELAY
OK -- Continue to next step.

7. INSPECT SKID CONTROL ECU CONNECTOR (STPO TERMINAL VOLTAGE)





(a) Install the stop light operation (DAC) relay.
(b) Disconnect the skid control ECU connector.
(c) Turn the ignition switch on (IG).
(d) Measure the voltage according to the value(s) in the table below.
Voltage:






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

8. RECONFIRM DTC
(a) Clear the DTC.
(b) Depress the brake pedal several times to test the stop light circuit.
(c) Check if the same DTC is detected.

HINT: Reinstall the sensors, connectors, etc. and restore the vehicle to its prior conditions before rechecking for DTCs.

Result:





B -- END
A -- REPLACE ABS & TRACTION ACTUATOR ASSEMBLY
9. INSPECT STOP LIGHT SWITCH ASSEMBLY (POWER SOURCE TERMINAL VOLTAGE)





(a) Disconnect the stop light switch connector.
(b) Measure the voltage according to the value(s) in the table below.
Voltage:






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

10. INSPECT STOP LIGHT SWITCH ASSEMBLY





(a) Disconnect the stop light switch assembly connector.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:





Result:





C -- REPLACE STOP LIGHT SWITCH ASSEMBLY
B -- CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH TO SKID CONTROL ECU)
A -- Continue to next step.

11. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH TO BRK RELAY)





(a) Remove the BRK relay.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH TO BRK RELAY)
OK -- Continue to next step.

12. INSPECT BRK RELAY





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






NG -- REPLACE BRK RELAY
OK -- Continue to next step.

13. CHECK HARNESS AND CONNECTOR (BETWEEN REAR COMBINATION LIGHT, BODY GROUND AND BRK RELAY)





(a) Disconnect the rear combination light connector.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:

LH:





RH:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT CIRCUIT)
OK -- END
14. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH TO SKID CONTROL ECU)





(a) Disconnect the stop light switch connector and skid control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH TO SKID CONTROL ECU)
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT CIRCUIT)