C1513

C1513

Component Location:

General Description
The brake light switch indicates brake pedal status to the ABS control unit.
The brake light switch which is dual switch type send brake light signal to HECU. The switch is turned on when brake is depressed.
The brake light switch runs to battery voltage when brake depressed. but The brake light switch doesn't run to battery voltage when brake is not depressed.

DTC Description
The brake light signal is a reference to judge driver's intention for braking and The HECU checks open or short circuit of brake light switch for normal ABS/ESC control.
If an error is present, the warning lamp will illuminate.

DTC Detecting Condition:

Specification:

Schematic Diagram:

Monitor Scantool Data
1. Connect scantool to Data Link Connector (DLC).
2. Ignition "ON" & Engine "OFF".
3. Press the brake pedal.
4. Monitor the "BRAKE SWITCH" parameter on the scantool.






5. Whenever brake pedal is pushed down, is the brake switch's scantool data changed ON/OFF?

YES - Fault is intermittent caused by poor connection in brake switch line or was repaired and HECU memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.

NO - Go to "W/Harness Inspection" procedure.

Terminal and Connector Inspection
1. Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?

YES - Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

NO - Go to "Signal Circuit Inspection" procedure.

Signal circuit inspection (brake pedal isn't depressed)
4. Ignition "ON" & Engine "OFF".
5. Press the brake pedal.
6. Measure voltage between the terminal "30" of the HECU harness connector and chassis ground.

Specification: Brake Light Switch - Approx. 0 V






7. Is the measured voltage within specifications?

YES - Go to "Signal Circuit Inspection (brake pedal is depressed)" procedure.

NO
- Check for open or blown 20 A STOP, 7.5 A SNSR fuse referring to "Circuit Diagram".
Check for open or short to battery between the battery terminal (+) and the terminal "30" of the HECU harness connector. Repair as necessary and then go to "Verification of vehicle Repair" procedure.
- If OK, Go to "Component Inspection" Procedure.

Signal circuit inspection (brake pedal is depressed)
8. Ignition "ON" & Engine "OFF".
9. Press the brake pedal.
10. Measure voltage between the terminal "30" of the HECU harness connector and chassis ground.

Specification: Brake Light Switch - Approx. B+






11. Is the measured voltage within specifications?

YES - Fault is intermittent caused by open or short harness in brake light switch, faulty brake light switch or was repaired and HECU memory was not cleared. Go to "Verification of Vehicle Repair" procedure.

NO
- Check for open or short to ground between the battery terminal (+) and the terminal "30" of the HECU harness connector. Repair as necessary and then go to "Verification of vehicle Repair" procedure.
- If OK, Go to "Component Inspection" Procedure.

Component Inspection
1. Ignition "OFF".
2. Disconnect brake switch connector.
3. Measure resistance between the terminal "2", "3" of the brake switch.

Specification: Resistance between the terminal "2, 3" of the brake switch - Infinity ohms (when the plunger is pushed down), 0 ohms (when the plunger isn't pushed down).






4. Is the measured voltage within specifications?

YES - Fault is intermittent caused by open or short harness in brake light switch, faulty brake light switch or was repaired and HECU memory was not cleared. Go to "Verification of Vehicle Repair" procedure.

NO - Substitute with a known-good brake lamp switch and check for proper operation. If problem is corrected, replace brake light switch and then go to "Verification of Vehicle Repair" procedure.

Verification of Vehicle Repair
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scantool and select "Diagnostic Trouble Codes (DTCs)" mode
2. Using a scantool, Clear DTC.
3. Operate the vehicle within DTC Detecting Condition in General Information.
4. Are any DTCs present?

YES - Go to the applicable troubleshooting procedure.

NO - System performing to specification at this time.