Code No.B1740, B1741: Blown turn-signal lamp bulb <COLT CZ3>




COMMENTS ON TROUBLE SYMPTOM


When the turn-signal lamp bulb is blown, or connector(s) or wiring harness between the ETACS-ECU, the turn-signal lamp which does not illuminate and body earth is defective, the ETACS-ECU sets diagnosis code No.B1740 (the right lamp is defective) or No.B1741 (the left lamp is defective).

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Confirm which turn-signal lamp is defective.

Q. Which turn-signal lamp fails to illuminate correctly?
Front turn-signal lamp : Go to Step 2.
Side turn-signal lamp : Go to Step 9.
Rear turn-signal lamp : Go to Step 16.
All lamps on the right side do not illuminate. : Go to Step 23.
All lamps on the left side do not illuminate. : Go to Step 24.

STEP 2. Connector check: A-10 and A-11 front combination lamp (turn: LH) connector or A-25 and A-26 front combination lamp (turn: RH) connector.


Q. Is the check result normal?

Go to Step 3.

Repair the defective connector. Go to Step 25.

STEP 3. Check the bulb(s) of the front turn-signal lamps.
Check the bulb(s) of the defective lamp.

Q. Is the check result normal?
Go to Step 4.
Replace the bulb(s) of the defective lamp. Go to Step 25.

STEP 4. Resistance measurement at A-11 front combination lamp (turn: LH) connector or A-25 front combination lamp (turn: RH) connector.


(1)Disconnect the connector, and measure at the wiring harness side.

(2)Resistance measurement between the defective lamp connector terminal and body earth.

  • Resistance between A-11 front combination lamp (turn: LH) connector terminal No.3 and body earth
  • Resistance between A-25 front combination lamp (turn: RH) connector terminal No.3 and body earth
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 6.

Go to Step 5.

STEP 5. Check the wiring harness from A-11 front combination lamp (turn: LH) connector terminal No.3 or A-25 front combination lamp (turn: RH) connector terminal No.3 to body earth.



  • Check the earth wires for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ). Go to Step 25.

Repair the wiring harness. Go to Step 25.

STEP 6. Connector check: B-234 ETACS-ECU connector


Q. Is the check result normal?

Go to Step 7.

Repair the defective connector. Go to Step 25.

STEP 7. Check the wiring harness from A-10 front combination lamp (turn: LH) connector terminal No.1, A-26 front combination lamp (turn: RH) connector terminal No.2 terminal No.1 to B-234 ETACS-ECU connector terminal No.3, No.4.






note Prior to the wiring harness inspection, check junction block connector B-212, and repair if necessary.

  • Check the output lines for open circuit.

Q. Is the check result normal?

Go to Step 8.

Repair the wiring harness. Go to Step 25.

STEP 8. Retest the system.
Check that the front turn-signal lamps illuminate normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ). Go to Step 25.
Replace the front combination lamp. Go to Step 25.

STEP 9. Connector check: A-07 side turn-signal lamp (LH) connector or A-01 side turn-signal lamp (RH) connector.


Q. Is the check result normal?

Go to Step 10.

Repair the defective connector. Go to Step 25.

STEP 10. Check the bulb(s) of side turn-signal lamps.
Check the bulb(s) of the defective lamp.

Q. Is the check result normal?
Go to Step 11.
Replace the bulb(s) of the defective lamp. Go to Step 25.

STEP 11. Resistance measurement at A-07 side turn-signal lamp (LH) connector or A-01 side turn-signal lamp (RH) connector.


(1)Disconnect the connector, and measure at the wiring harness side.

(2)Resistance measurement between the defective lamp connector terminal and body earth.

  • Resistance between A-07 side turn-signal lamp (LH) connector terminal No.2 and body earth
  • Resistance between A-01 side turn-signal lamp (RH) connector terminal No.2 and body earth
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 13.

Go to Step 12.

STEP 12. Check the wiring harness from A-07 side turn-signal lamp (LH) connector terminal No.2 or A-01 side turn-signal lamp (RH) connector terminal No.2 and body earth.



  • Check the earth wires for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).

Repair the wiring harness. Go to Step 25.

STEP 13. Connector check: B-234 ETACS-ECU connector


Q. Is the check result normal?

Go to Step 14.

Repair the defective connector. Go to Step 25.

STEP 14. Check the wiring harness from A-07 side turn-signal lamp (LH) connector terminal No.1, A-01 side turn-signal lamp (RH) connector terminal No.1 to B-234 ETACS-ECU connector terminal No.3, No.4.






note Prior to the wiring harness inspection, check junction block connector B-212, and repair if necessary.

  • Check the output lines for open circuit.

Q. Is the check result normal?

Go to Step 15.

Repair the wiring harness. Go to Step 25.

STEP 15. Retest the system.
Check that the side turn-signal lamps illuminate normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ). Go to Step 25.
Replace the side turn-signal lamp. Go to Step 25.

STEP 16. Connector check: C-37 rear combination lamp (turn: LH) or C-36 rear combination lamp (turn: RH).

Q. Is the check result normal?

Go to Step 17.

Repair the defective connector. Go to Step 25.

STEP 17. Check the bulb(s) of rear turn-signal lamps.
Check the bulb(s) of the defective lamp.

Q. Is the check result normal?
Go to Step 18.
Replace the bulb(s) of the defective lamp. Go to Step 25.

STEP 18. Resistance measurement at C-37 rear combination lamp (turn: LH) connector or C-36 rear combination lamp (turn: RH) connector.

(1)Disconnect the connector, and measure at the wiring harness side.


(2)Resistance measurement between the defective lamp connector terminal and body earth.

  • Resistance between C-37 rear combination lamp (turn: LH) connector terminal No.2 and body earth
  • Resistance between C-36 rear combination lamp (turn: RH) connector terminal No.1 and body earth
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 20.

Go to Step 19.

STEP 19. Check the wiring harness from C-37 rear combination lamp (turn: LH) connector terminal No.2 or C-36 rear combination lamp (turn: RH) connector terminal No.1 to body earth.


  • Check the earth wires for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ). Go to Step 25.

Repair the wiring harness. Go to Step 25.

STEP 20. Connector check: B-234 ETACS-ECU connector


Q. Is the check result normal?

Go to Step 21.

Repair the defective connector. Go to Step 25.

STEP 21. Check the wiring harness from C-37 rear combination lamp (turn: LH) connector terminal No.4, C-36 rear combination lamp (turn: RH) connector terminal No.3 to B-234 ETACS-ECU connector terminal No.3, No.4.



note Prior to the wiring harness inspection, check junction block connector B-228, and repair if necessary.

  • Check the output lines for open circuit.

Q. Is the check result normal?

Go to Step 22.

Repair the wiring harness. Go to Step 25.

STEP 22. Retest the system.
Check that the rear turn-signal lamps illuminate normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ). Go to Step 25.
Replace the rear combination lamp. Go to Step 25.

STEP 23. Check the wiring harness from A-26 front combination lamp (turn: RH) connector terminal No.1, A-01 side turn-signal lamp (RH) connector terminal No.1, C-36 rear combination lamp (turn: RH) connector terminal No.3 to B-234 ETACS-ECU connector terminal No.4.






note Prior to the wiring harness inspection, check junction block connectors B-212 and B-228, and repair if necessary.

  • Check the output lines for short circuit.

Q. Is the check result normal?

Go to Step 25.

Repair the wiring harness. Go to Step 25.

STEP 24. Check the wiring harness from A-10 front combination lamp (turn: LH) connector terminal No.1, A-07 side turn-signal lamp (LH) connector terminal No.1, C-37 rear combination lamp (turn: LH) connector terminal No.4 to B-234 ETACS-ECU connector terminal No.3.






note Prior to the wiring harness inspection, check junction block connectors B-212 and B-228, and repair if necessary.

  • Check the output lines for short circuit.

Q. Is the check result normal?

Go to Step 25.

Repair the wiring harness. Go to Step 25.

STEP 25. Check whether the diagnosis code is reset.
Check if diagnosis code No.B1740 or B1741 is set.

Q. Is the diagnosis code set?
Replace the ETACS-ECU. Then perform the variant coding and write the VIN data (Refer to GROUP 00, Precautions Before Service - How to Perform Variant Coding ).
The procedure is complete.