Code No.C1340: Stop lamp switch error




caution
  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C, CAN Bus Diagnosis Table ).
  • Whenever ECU is replaced, ensure that the CAN bus lines are normal.

OPERATION
TCL/ASC-ECU monitors the ON/OFF signals from the stop lamp switches (brake control system and cruise control system) and the pressure sensor (incorporated in the hydraulic unit).

DIAGNOSIS CODE SET CONDITIONS
This diagnosis code is set in the following case.

  • When both of the signals from the stop lamp switches (brake control system and cruise control system) are ON.
  • When the signal that the brake pressure is applied is received from the pressure sensor (incorporated in the hydraulic unit) although the signal from the stop lamp switch (brake control system) is OFF.

PROBABLE CAUSES

  • Improper adjustment of stop lamp switch installation position
  • Stop lamp switch malfunction
  • Damaged wiring harness and connectors
  • TCL/ASC-ECU malfunction

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?
Go to Step 3.
Repair the CAN bus lines. (Refer to GROUP 54C - CAN Bus Diagnosis table .) On completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting CAN bus lines

Q. Is diagnosis code No.C1340 set?
Go to Step 3.
This diagnosis is complete.

STEP 3. Battery check
Refer to GROUP 54A - Battery Test .

Q. Is the battery in good condition?
Go to Step 4.
Charge or replace the battery. Then go to Step 23.

STEP 4. Stop lamp operation check
Check the stop lamp operation when the brake pedal is depressed. Check that all the stop lamp illuminates when the brake pedal is depressed and that it goes out when the brake pedal is released.
OK:
    When the brake pedal is released: OFF
    When the brake pedal is depressed: Illuminates

Q. Is the check result normal?
Go to Step 17.
Go to Step 5.

STEP 5. Check for stop lamp switch installation
Refer to GROUP 35A - On-vehicle Service .

Q. Is the check result normal?
Go to Step 6.
Install the stop lamp switch correctly. (Refer to GROUP 35A - On-vehicle Service .) Then go to Step 23.

STEP 6. Stop lamp switch continuity check
(1)Remove the stop lamp switch. (Refer to GROUP 35A - Brake Pedal .)

(2)Connect the circuit tester (Ω range) to the stop lamp switch connector terminals No.1 and 6 or No. 3 and 4.
(3)Check for continuity between the terminals of the switch.
Check condition
 Terminal connector of tester
 Normal condition
When the switch knob is depressed fully
 1 - 6
 Continuity exists
(2 Ω or less)
3 - 4
 No continuity
When the switch knob is returned 2.8 mm or more
 1 - 6
 No continuity
When the switch knob is returned 4 mm or more
 3 - 4
 Continuity exists
(2 Ω or less)

Q. Is the check result normal?

Go to Step 7.

Replace the stop lamp switch. (Refer to GROUP 35A - Brake Pedal .) Then go to Step 23.

STEP 7. Junction block fuse No.42 check

Q. Is the check result normal?
Go to Step 12.
Go to Step 8.

STEP 8. Connector check: B-208 junction block connector, B-212 junction block connector, B-116 stop lamp switch connector, B-118 Intermediate connector, B-24 joint connector, E-04 rear combination lamp (stop: RH) connector <COLT>, C-36 rear combination lamp (stop: RH) connector <COLT CZ3>, E-01 rear combination lamp (stop: LH) connector <COLT>, C-37 rear combination lamp (stop: LH) connector <COLT CZ3>, E-03 highmounted stop lamp connector, A-06 TCL/ASC-ECU connector









Q. Is the check result normal?

Go to Step 9.

Repair the damaged connector, and then replace fuse No.42. Then go to Step 23 .

STEP 9. Resistance measurement at B-116 stop lamp switch connector


(1)Disconnect B-116 stop lamp switch connector, and measure at the wiring harness side.


(2)Disconnect B-212 junction block connector.

(3)Measure the resistance between the terminal No.4 and the body earth.
OK: No continuity

Q. Is the check result normal?

Go to Step 10.

An short to power supply line may be present in the wiring harness between B-212 junction block connector terminal No.22 and B-116 stop lamp switch connector terminal No.4. Repair the wiring harness, and then replace fuse No.42. Then go to Step 23.

STEP 10. Resistance measurement at B-116 stop lamp switch connector


(1)Disconnect B-116 stop lamp switch connector, and measure at the wiring harness side.

(2)Disconnect A-06 TCL/ASC-ECU connector and B-24 joint connector.

(3)Measure the resistance between the terminal No.3 and the body earth.
OK: No continuity

Q. Is the check result normal?

Go to Step 11.

An short circuit may be present in the wiring harness between B-116 stop lamp switch connector terminal No.3 and A-06 TCL/ASC-ECU connector terminal No.6, or between B-116 stop lamp switch connector terminal No.3 and B-24 joint connector terminal No.11. Repair the wiring harness, and then replace fuse No.42. Then go to Step 23.

STEP 11. Resistance measurement at B-24 joint connector


(1)Disconnect B-24 joint connector, and measure at the wiring harness side.



(2)Disconnect E-04 rear combination lamp (stop: RH) connector <COLT>, C-36 rear combination lamp (stop: RH) connector <COLT CZ3>, E-01 rear combination lamp (stop: LH) connector <COLT>, C-37 rear combination lamp (stop: LH) connector <COLT CZ3>, E-03 highmounted stop lamp connector.

(3)Measure the resistance between the terminal No.11 and the body earth.
OK: No continuity

Q. Is the check result normal?

Replace fuse No.42. Then go to Step 23.

An short circuit may be present in the wiring harness between B-24 joint connector terminal No.11 and E-04 rear combination lamp (stop: RH) connector terminal No.5 <COLT> or C-36 rear combination lamp (stop: RH) connector terminal No.4 <COLT CZ3> or E-01 rear combination lamp (stop: LH) connector terminal No.2 <COLT> or C-37 rear combination lamp (stop: LH) connector terminal No.1 <COLT CZ3> or E-03 highmounted stop lamp connector terminal No.2. Repair the wiring harness, and then replace fuse No.42. Then go to Step 23.

STEP 12. Connector check: B-208 junction block connector, B-212 junction block connector, B-116 stop lamp switch connector, A-06 TCL/ASC-ECU connector





Q. Is the check result normal?

Go to Step 13.

Repair the damaged connector. Then go to Step 23.

STEP 13. Measure the voltage at the B-208 junction block connector.


caution Measure while the brake pedal is not depressed.
Measure the voltage between terminal No. 1 and the body earth by backprobing.
OK: System voltage

Q. Is the check result normal?

Go to Step 14.

An open circuit may be present in the wiring harness between B-208 junction block connector terminal No.1 and fusible link No.1. Repair the wiring harness. Then go to Step 23 .

STEP 14. Measure the voltage at B-116 stop lamp switch connector.


(1)Disconnect B-116 stop lamp switch connector, and measure the voltage at harness connector side.

(2)Measure the voltage between the terminal No.4 and the body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 15.

An open circuit may be present in the wiring harness between B-116 stop lamp switch connector terminal No.4 and B-212 junction block connector terminal No. 22. Repair the wiring harness. Then go to Step 15.

STEP 15. Measure the voltage at B-24 joint connector.


(1)Disconnect B-24 joint connector, and measure the voltage at harness connector side.

(2)Measure the voltage between the terminal No.11 and the body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 16.

An open circuit may be present in the wiring harness between B-116 stop lamp switch connector terminal No.3 and B-24 joint connector terminal No. 11. Repair the wiring harness. Then go to Step 16.

STEP 16. Measure the voltage at E-04 rear combination lamp (stop: RH) connector <COLT>, C-36 rear combination lamp (stop: RH) connector <COLT CZ3>, E-01 rear combination lamp (stop: LH) connector <COLT>>, C-37 rear combination lamp (stop: LH) connector <COLT CZ3>, E-03 highmounted stop lamp connector .



(1)Disconnect E-04 rear combination lamp (stop: RH) connector <COLT>, C-36 rear combination lamp (stop: RH) connector <COLT CZ3>, E-01 rear combination lamp (stop: LH) connector <COLT>, C-37 rear combination lamp (stop: LH) connector <COLT CZ3>, E-03 highmounted stop lamp connector, and measure the voltage at harness connector side.





(2)Measure the voltage between the E-04 rear combination lamp (stop: RH) connector terminal No.5 <COLT>, C-36 rear combination lamp (stop: RH) connector terminal No.4 <COLT CZ3>, E-01 rear combination lamp (stop: LH) connector terminal No.2 <COLT>, C-37 rear combination lamp (stop: LH) connector terminal No.1 <COLT CZ3>, E-03 highmounted stop lamp connector terminal No.2 and the body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 18.

An open circuit may be present in the wiring harness between B-24 junction connector terminal No.8, 9 10 and E-04 rear combination lamp (stop: RH) connector terminal No.5 <COLT>, C-36 rear combination lamp (stop: RH) connector terminal No.4 <COLT CZ3>, E-01 rear combination lamp (stop: LH) connector terminal No.2 <COLT>, C-37 rear combination lamp (stop: LH) connector terminal No.1 <COLT CZ3>, E-03 highmounted stop lamp connector terminal No.2. Repair the wiring harness. Then go to Step 23 .

STEP 17. Connector check: A-06 TCL/ASC-ECU connector

Q. Is the check result normal?

Go to Step 18.

Repair the damaged connector. Then go to Step 23.

STEP 18. Measure the voltage at the A-06 TCL/ASC-ECU connector.

(1)Disconnect the TCL/ASC-ECU connector, connect special tool ABS check harness (MB991951) to the harness-side connector, and then measure the voltage at the special tool connector side.
note Do not connect the special tool ABS check harness (MB991951) to TCL/ASC-ECU.
(2)Turn the ignition switch to the ON position.

(3)Measure the voltage between the terminal No.6 and the body earth.
OK:
    When the brake pedal is released: 1 V or less
    When the brake pedal is depressed: System voltage

Q. Is the check result normal?

Go to Step 19.

An open circuit may be present in the wiring harness between B-116 stop lamp switch connector terminal No.3 and A-06 TCL/ASC-ECU connector terminal No.6. Repair the wiring harness. Then go to Step 23.

STEP 19. Measure the voltage at B-116 stop lamp switch connector.


(1)Disconnect B-116 stop lamp switch connector, and measure the voltage at harness connector side.
(2)Turn the ignition switch to the ON position.

(3)Measure the voltage between the terminal No.6 and the body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 21.

An open circuit may be present in the wiring harness between B-116 stop lamp switch connector terminal No.6 and A-06 TCL/ASC-ECU connector terminal No. 23. Repair the wiring harness. Then go to Step 20.

STEP 20. Resistance measurement at B-116 stop lamp switch connector


(1)Disconnect B-116 stop lamp switch connector, and measure at the wiring harness side.

(2)Disconnect A-06 TCL/ASC-ECU connector.

(3)Measure the resistance between the terminal No.6 and the body earth.
OK: No continuity

Q. Is the check result normal?

Go to Step 21.

An short circuit may be present in the wiring harness between B-116 stop lamp switch connector terminal No.6 and A-06 TCL/ASC-ECU connector terminal No.23. Repair the wiring harness. Then go to Step 21.

STEP 21. Resistance measurement at B-116 stop lamp switch connector


(1)Disconnect B-116 stop lamp switch connector, and measure at the wiring harness side.

(2)Measure the resistance between the terminal No.1 and the body earth.
OK: Continuity

Q. Is the check result normal?

Go to Step 22.

An open circuit may be present in the wiring harness between B-116 stop lamp switch connector terminal No.1 and body earth. Replace the wiring harness. Then go to Step 23.

STEP 22. Diagnosis code recheck

Q. Is diagnosis code No.C1340 set?
Replace the hydraulic unit (TCL/ASC-ECU) (Refer to ). Then go to Step 23.
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction .)

STEP 23. Diagnosis code recheck

Q. Is diagnosis code No.C1340 set?
Return to Step 1.
This diagnosis is complete.