B16A8

DTC B16A1: Taillight (LH) Circuit Open [Open Circuit In The Position Light (LH) Circuit, Rear Side Marker Light (LH) Circuit, Taillight (LH) And The License Plate Light Circuit]
DTC B16A8: Taillight (LH) Circuit Short [Short Circuit In The Position Light (LH) Circuit, Rear Side Marker Light (LH) Circuit, Taillight (LH) Circuit Or The License Plate Light Circuit]

Tail Light (LH) Circuit (Part 1):

Tail Light (LH) Circuit (Part 2):

TROUBLE JUDGMENT
When an open circuit is detected in the taillight circuit, the ETACS-ECU sets DTC B16A1. If a short circuit is detected, DTC B16A8 is set.

TECHNICAL DESCRIPTION (COMMENT)
The problem detection of taillight is made based on the digital feed back signal (input signal to ETACS-ECU) which operates the taillight. When the ignition switch is "ON", the ETACS-ECU determines the taillight circuit state from the load placed on the line. After 100 ms has elapsed since the start of the check, the ETACS-ECU performs a sampling with each 10 ms. If an abnormality is detected, it increases the counter by 2, and when no abnormality is detected, it decreases the counter by 1. Once the counter reaches "10", the ETACS-ECU sets the DTC B16A1 if the load is detected on the line, and sets the DTC B16A8 if no load is detected.

TROUBLESHOOTING HINTS
- Malfunction of bulbs
- Malfunction of rear combination light unit (LH)
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
- Malfunction of the ETACS-ECU

DIAGNOSIS

Required Special Tools:
- MB992006: Extra fine probe
- MB991223: Harness set
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

STEP 1. Bulb check.

Check the bulb of the light that does not illuminate.

Q: Is the check result normal?

YES : Go to Step 2.

NO : Replace the bulb of the light that does not illuminate.

STEP 2. Check headlight assembly (LH) connector A-37 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is headlight assembly (LH) connector A-37 in good condition?

YES : Go to Step 3.

NO : Repair the damaged parts.

STEP 3. Resistance measurement at headlight assembly (LH) connector A-37.

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




2. Measure the resistance between headlight assembly (LH) connector A-37 (terminal No. 8) and the body ground.
The measured value should be continuity exists (2 ohms or less).

Q: Does the measured resistance value correspond with this range?

YES : Go to Step 5.

NO : Go to Step 4.

STEP 4. Check the wiring harness between headlight assembly (LH) connector A-37 (terminal No. 8) and ground.

Q: Is the wiring harness between headlight assembly (LH) connector A-37 (terminal No. 8) and ground in good condition?

YES : Go to Step 22.

NO : Repair the wiring harness.

STEP 5. Check ETACS-ECU connectors C-304 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is ETACS-ECU connectors C-304 in good condition?

YES : Go to Step 6.

NO : Repair the damaged parts.

STEP 6. Check the wiring harness between headlight assembly (LH) A-37 connector (terminal No. 6) and ETACS-ECU connector C-304 (terminal No. 3).

Q: Is the wiring harness between headlight assembly (LH) A-37 connector (terminal No. 6) and ETACS-ECU connector C-304 (terminal No. 3) in good condition?

YES : Go to Step 7.

NO : Repair the wiring harness.

STEP 7. Check rear side marker light (LH) connector F-16 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is rear side marker light (LH) connector F-16 in good condition?

YES : Go to Step 8.

NO : Repair the damaged parts.

STEP 8. Resistance measurement at rear side marker light (LH) connector F-16.

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




2. Measure the resistance between rear side marker light (LH) connector F-16 (terminal No. 1) and the body ground.
The measured value should be continuity exists (2 ohms or less).

Q: Does the measured resistance value correspond with this range?

YES : Go to Step 10.

NO : Go to Step 9.

STEP 9. Check the wiring harness between rear side marker light (LH) connector F-16 (terminal No. 1) and ground.

NOTE: Before the wiring harness check, check the F-15, F-18 and repair that if necessary.

Q: Is the wiring harness between rear side marker light (LH) connector F-16 (terminal No. 1) and ground in good condition?

YES : Go to Step 22.

NO : Repair the wiring harness.

STEP 10. Check ETACS-ECU connectors C-311 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is ETACS-ECU connectors C-311 in good condition?

YES : Go to Step 11.

NO : Repair the damaged parts.

STEP 11. Check the wiring harness between rear side marker light (LH) F-16 connector (terminal No. 2) and ETACS-ECU connector C-311 (terminal No. 10).

NOTE: Before the wiring harness check, check the F-15, F-18 and repair that if necessary.

Q: Is the wiring harness between rear side marker light (LH) F-16 connector (terminal No. 2) and ETACS-ECU connector C-311 (terminal No. 10) in good condition?

YES : Go to Step 12.

NO : Repair the wiring harness.

STEP 12. Check license plate light (LH) connector F-03 and license plate light (RH) connector F-07 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is license plate light (LH) connector F-03 and license plate light (RH) connector F-07 in good condition?

YES : Go to Step 13.

NO : Repair the damaged parts.

STEP 13. Resistance measurement at license plate light (LH) connector F-03 and license plate light (RH) connector F-07.

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




2. Measure the resistance between license plate light connector F-03 (LH), F-07 (RH) (terminal No. 1) and the body ground.
The measured value should be continuity exists (2 ohms or less).

Q: Does the measured resistance value correspond with this range?

YES : Go to Step 15.

NO : Go to Step 14.

STEP 14. Check the wiring harness between license plate light connector F-03 (LH) or F-07 (RH) (terminal No. 1) and ground.

Q: Is the wiring harness between license plate light connector F-03 (LH) or F-07 (terminal No. 1) and ground in good condition?

YES : Go to Step 22.

NO : Repair the wiring harness.

STEP 15. Check ETACS-ECU connectors C-311 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is ETACS-ECU connectors C-311 in good condition?

YES : Go to Step 16.

NO : Repair the damaged parts.

STEP 16. Check the wiring harness between license plate light connector F-03 (LH), F-07 (RH) (terminal No. 2) and ETACS-ECU connector C-311 (terminal No. 10).

NOTE: Before the wiring harness check, check the D-12 and repair that if necessary.

Q: Is the wiring harness between license plate light connector F-03 (LH), F-07 (RH) (terminal No. 2) and ETACS-ECU connector C-311 (terminal No. 10) in good condition?

YES : Go to Step 17.

NO : Repair the wiring harness.

STEP 17. Check rear combination light (LH) connector D-14 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is combination light (LH) connector D-14 in good condition?

YES : Go to Step 18.

NO : Repair the damaged parts.

STEP 18. Resistance measurement at rear combination light (LH) connector D-14.

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




2. Measure the resistance between rear combination light (LH) connector D-14 (terminal No. 4) and the body ground.
The measured value should be continuity exists (2 ohms or less).

Q: Does the measured resistance value correspond with this range?

YES : Go to Step 20.

NO : Go to Step 19.

STEP 19. Check the wiring harness between rear combination light (LH) connector D-14 (terminal No. 4) and ground.

Q: Is the wiring harness between rear combination light (LH) connector D-14 (terminal No. 4) and ground in good condition?

YES : Go to Step 22.

NO : Repair the wiring harness.

STEP 20. Check ETACS-ECU connectors C-311 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is ETACS-ECU connectors C-311 in good condition?

YES : Go to Step 21.

NO : Repair the damaged parts.

STEP 21. Check the wiring harness between rear combination light (LH) D-14 connector (terminal No. 2) and ETACS-ECU connector C-311 (terminal No. 10).

Q: Is the wiring harness between rear combination light (LH) D-14 connector (terminal No. 2) and ETACS-ECU connector C-311 (terminal No. 10) in good condition?

YES : Go to Step 22.

NO : Repair the wiring harness.

STEP 22. Using scan tool MB991958, Check whether the diagnostic trouble code is reset.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.




1. Connect scan tool MB991958. Refer to "How to connect scan tool." Scan Tool Connecting
2. Turn the ignition switch to the "ON" position.
3. Erase the DTC.
4. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
5. Check if DTC is set.

Q: Is the DTC set?

YES : Go to Step 23.

NO : The trouble can be an intermittent malfunction (Refer to general (body and chassis) - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction).

STEP 23. Substitute a known good rear combination light unit (LH), and Using scan tool MB991958, Check whether the diagnostic trouble code is reset.

1. Turn the ignition switch to the "ON" position.
2. Erase the DTC.
3. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
4. Check if DTC is set.

Q: Is the DTC set?

YES : Replace the ETACS-ECU.

NO : Replace the rear combination light unit (LH).