C1249
BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: 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 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 an open circuit is detected in the stop light switch input circuit while the stop light switch is OFF.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE: When replacing the skid control ECU, perform zero point calibration and store system information Testing and Inspection.
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 SW FUSE
OK -- Continue to next step.
2. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH AND BRAKE PEDAL LOAD SENSING SWITCH)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Select the Data List mode on the Techstream Data List / Active Test.
ABS/VSC/TRAC
(d) Check that the stop light display observed on the Techstream changes when the brake pedal is depressed.
OK:
When the brake pedal is depressed, the Techstream displays "ON".
(e) Depress the brake pedal slowly, and check when the stop light switch and brake pedal load sensing switch turn ON.
OK:
First the stop light switch should turn ON, and then the brake pedal load sensing switch should turn ON.
Result:
C -- CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION
B -- CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE ROOM NO. 3 RELAY BLOCK)
A -- Continue to next step.
3. INSPECT SKID CONTROL ECU (IG1 TERMINAL)
(a) Turn the engine switch off.
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(c) Disconnect the skid control ECU connector.
(d) Turn the engine switch on (IG).
(e) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)
OK -- Continue to next step.
4. INSPECT SKID CONTROL ECU (GND TERMINAL)
(a) Turn the engine 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 connectors.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)
OK -- Continue to next step.
5. RECONFIRM DTC
(a) Reconnect the skid control ECU connectors.
(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 Problem Symptoms Table, refer back to the table and proceed to the next step Problem Symptoms Table.
B -- REPLACE SKID CONTROL ECU
A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)
6. INSPECT STOP SW FUSE
(a) Remove the STOP SW fuse from the main body ECU RH (cowl side junction block RH).
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPLACE STOP SW FUSE
OK -- Continue to next step.
7. INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL)
(a) Install the STOP SW fuse.
(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:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
OK -- Continue to next step.
8. INSPECT STOP LIGHT SWITCH
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPLACE STOP LIGHT SWITCH
OK -- Continue to next step.
9. INSPECT STOP LIGHT CONTROL RELAY (BRK-LP)
(a) Remove the stop light control (BRK-LP) relay.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
NG -- REPLACE STOP LIGHT CONTROL RELAY (BRK-LP)
OK -- Continue to next step.
10. INSPECT STOP LIGHT CONTROL RELAY
(a) Check the stop light control relay Testing and Inspection.
OK:
The stop light control relay is normal.
NG -- REPLACE STOP LIGHT CONTROL RELAY
OK -- Continue to next step.
11. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - STOP LIGHT CONTROL RELAY)
(a) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(b) Disconnect the stop light control relay 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.
12. CHECK HARNESS AND CONNECTOR (STOP LIGHT CONTROL RELAY - ENGINE ROOM NO. 3 RELAY BLOCK)
(a) 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.
13. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE ROOM NO. 3 RELAY BLOCK)
(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.
14. 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 recorded Reading and Clearing Diagnostic Trouble Codes.
HINT: Reinstall the relay, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.
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 SKID CONTROL ECU
A -- INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT)
15. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE ROOM NO. 3 RELAY BLOCK)
(a) Turn the engine switch off.
(b) Remove the stop light control (BRK-LP) relay.
(c) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(d) Disconnect the skid control ECU connector.
(e) 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 SKID CONTROL ECU
16. CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION
(a) Turn the engine switch off.
(b) Check the brake pedal height and stop light switch installation Adjustments.
OK:
The brake pedal height and stop light switch installation are normal.
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 -- ADJUST BRAKE PEDAL OR STOP LIGHT SWITCH
OK -- REPLACE BRAKE PEDAL SUPPORT ASSEMBLY (BRAKE PEDAL LOAD SENSING SWITCH)