S-AWC (Super All Wheel Control)
DTC C1000: Stoplight Switch System
CAUTION:
- If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines.
- Whenever the ECU is replaced, ensure that the CAN bus lines are normal.
OPERATION
AWC-ECU receives signals of stoplight switch from ETACS-ECU via the CAN bus lines.
DTC SET CONDITIONS
This diagnostic trouble code is set when the abnormality below is detected:
- The vehicle has run for a long time with the stop light switch turned "ON".
- With the stoplight switch "OFF", the vehicle speed is decelerated suddenly.
PROBABLE CAUSES
- Incorrect adjustment of stoplight switch position
- Malfunction of stoplight switch
- Stoplight malfunction
- Damaged harness wires and connectors
- Malfunction of the ETACS-ECU
- Malfunction of AWC-ECU
DIAGNOSTIC PROCEDURE
STEP 1. Scan tool CAN bus diagnostics
Using scan tool MB991958, diagnose the CAN bus lines.
Q. Is the check result normal?
YES Go to Step 3.
NO Repair the CAN bus lines CAN Bus Diagnostics Chart).
After repairing the CAN bus line, go to Step 2.
STEP 2. Check whether the DTC is reset.
Q. Is DTC No. C1000 set?
YES Go to Step 3.
NO This diagnosis is complete.
STEP 3. Check of the stoplight on and off
Check that the stoplight illuminates when the brake pedal is depressed, and the stoplight goes out when the brake pedal is released.
Q. Is the check result normal?
YES Go to Step 14.
NO Go to Step 4.
STEP 4. Stop light switch installation status check
Brake Pedal Inspection.
Q. Is the check result normal?
YES Go to Step 5.
NO Install the stop light switch correctly. Then go to Step 19.
STEP 5. Check the stop light switch.
Testing and Inspection.
Q. Is the check result normal?
YES Go to Step 6.
NO Replace the stoplight switch Service and Repair).
Then go to Step 19.
STEP 6. ETACS-ECU connector check: C-304
Q. Is the check result normal?
YES Go to Step 7.
NO Repair the defective connector. Then go to Step 19.
STEP 7. Measure the voltage at the C-304 ETACS-ECU connector.
With C-304 ETACS-ECU connector connected, measure the voltage between the terminal No. 1 and the body ground.
OK: Battery voltage (when the brake pedal is released)
Q. Is the check result normal?
YES Go to Step 10.
NO Go to Step 8.
STEP 8. ETACS-ECU fuse No. 2 check
Q. Is the check result normal?
YES Replace the ETACS-ECU Electronic Time and Alarm Control System (ETACS).
Then go to Step 19.
NO Replace fuse No. 2. Then go to Step 9.
STEP 9. Check the wiring harness between C-304 ETACS-ECU connector terminal No. 1 and C-48 stoplight switch connector terminal No. 2.
Check that the wiring harness is not shorted (short to ground).
Q. Is the check result normal?
YES Go to Step 19.
NO Repair the wiring harness. Then go to Step 19.
STEP 10. Stop light switch connector check: C-48
Q. Is the check result normal?
YES Go to Step 11.
NO Repair the defective connector. Then go to Step 19.
STEP 11. Voltage measurement at the C-48 stoplight switch connector
Disconnect the connector, and measure the voltage between terminal No. 2 and ground at the wiring harness side.
OK: Battery positive voltage
Q. Is the check result normal?
YES Go to Step 13.
NO Go to Step 12.
STEP 12. Check the wiring harness between C-304 ETACS-ECU connector terminal No. 1 and C-48 stoplight switch connector terminal No. 2.
Check the wiring harness for open circuit.
Q. Is the check result normal?
YES Go to Step 13.
NO Repair the wiring harness. Then go to Step 19.
STEP 13. Intermediate connector check: C-47
Q. Is the check result normal?
YES Go to Step 14.
NO Repair the defective connector. Then go to Step 19.
STEP 14. ETACS-ECU connector check: C-312
Q. Is the check result normal?
YES Go to Step 15.
NO Repair the defective connector. Then go to Step 19.
STEP 15. Measure the voltage at the C-312 ETACS-ECU connector.
Measure the voltage between C-312 ETACS-ECU connector terminal No. 16 and the body ground.
- OK: 1 V or less (brake pedal released)
- OK: Battery positive voltage (brake pedal depressed)
Q. Is the check result normal?
YES Go to Step 17.
NO Go to Step 16.
STEP 16. Check the wiring harness between C-312 ETACS-ECU connector terminal No. 16 and C-48 stoplight switch connector terminal No. 1.
Check the wiring harness for open circuit.
Q. Is the check result normal?
YES Go to Step 17.
NO Repair the wiring harness. Then go to Step 19.
STEP 17. Scan tool service data
Item No. 39: Stoplight switch (Refer to service data reference table Data List Reference Table)
Q. Is the check result normal?
YES Go to Step 18.
NO Replace the ETACS-ECU Electronic Time and Alarm Control System (ETACS).
Then go to Step 19.
STEP 18. Check whether the DTC is reset.
Q. Is DTC No. C1000 set?
YES Replace the AWC-ECU(Refer to Active Center Differential (ACD)). Then go to Step 19.
NO Intermittent malfunction How to Cope With Intermittent Malfunctions).
STEP 19. Check whether the DTC is reset.
Q. Is DTC No. C1000 set?
YES Return to Step 1.
NO This diagnosis is complete.