B16A2

DTC B16A2: Blown turn-signal light (LH) bulb


























TROUBLE JUDGMENT

When the left bulb of turn-signal light is blown, the ETACS-ECU sets DTC B16A2.

TECHNICAL DESCRIPTION (COMMENT)

The ETACS-ECU sets DTC B16A2 under the following conditions.

- If there is a malfunction to the left turn-signal light bulb, the blown left bulb counter counts once when the illumination of hazard or turn-signal light
(left side) is attempted.

- After the bulb counter reaches "3," DTC B16A2 is set.

TROUBLESHOOTING HINTS

- Malfunction of turn-signal light bulb (left)

- Malfunction of the ETACS-ECU

- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector

DIAGNOSIS

Required Special Tools:

- 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 whether the left turn-signal light illuminates normally.

Q. Is the check result normal?

YES Go to Step 2.
NO Replace the bulb of turn-signal light which does not illuminate.
STEP 2. Check headlight assembly (LH) connector A-37, side turn-signal light (LH) connector A-10 [fender type], door mirror assembly (LH) connector E-29 [door mirror type], rear combination light (LH) connector D-14 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Are headlight assembly (LH) connector A-37, side turn-signal light (LH) connector A-10 [fender type], door mirror assembly (LH) connector E-29 [door mirror type], rear combination light (LH) connector D-14 in good condition?

YES Go to Step 3.
NO : Repair the damaged parts.
STEP 3. Resistance measurement at headlight assembly (LH) connector A-37, side turn-signal light (LH) connector A-10 [fender type], door mirror assembly (LH) connector E-29 [door mirror type], rear combination light (LH) connector D-14.

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

















(2)Measure the resistance between the connector terminal of light which does not illuminate and ground.

- Measure the resistance between the headlight assembly (LH) connector A-37 (terminal No.
6) and body ground.

- Measure the resistance between side turn-signal light (LH) connector A-10 (terminal No.
1) and body ground. [fender type]

- Measure the resistance between door mirror assembly (LH) connector E-29 (terminal No.
10) and body ground. [door mirror type]

- Measure the resistance between rear combination light (LH) connector D-14 (terminal No.
4) and body ground.
The measured value should be 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. 6), side turn-signal light (LH) connector A-10 (terminal No. 1) [fender type], door mirror assembly (LH) connector E-29 (terminal No. 10) [door mirror type], rear combination light (LH) connector D-14 (terminal No. 4) and ground.

Check the ground wires for open circuit.

NOTE:
Also check intermediate connector C-126 [door mirror type] for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-126 [door mirror type] is damaged, repair or replace the connector as described in Harness Connector Inspection Harness Connector Inspection.

Q. Are the wiring harness between headlight assembly (LH) connector A-37 (terminal No.
6), side turn-signal light (LH) connector A-10 (terminal No. 1) [fender type], door mirror assembly (LH) connector E-29 (terminal No. 10) [door mirror type], rear combination light
(LH) connector D-14 (terminal No. 4) and ground in good condition?

YES Go to Step 7.
NO Repair the wiring harness.
STEP 5. Check ETACS-ECU connectors C-304, C-311 and C-317 [door mirror type] for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Are ETACS-ECU connectors C-304, C-311 and C-317 in good condition?

YES Go to Step 6.
NO Repair the damaged parts.
STEP 6. Check the wiring harness between headlight assembly (LH) connector A-37 (terminal No. 3), side turn-signal light (LH) connector A-10 (terminal No. 2) [fender type], door mirror assembly (LH) connector E-29 (terminal No. 2) [door mirror type], rear combination light (LH) connector D-14 (terminal No. 3) and ETACS-ECU connector C-304 (terminal No. 9), ETACS-ECU connector C-311 (terminal No. 18) or ETACS-ECU connector C-317 (terminal No.
4).

Check the communication line for open circuit.

NOTE:
Also check intermediate connector C-127 [door mirror type] for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-127 [door mirror type] is damaged, repair or replace the connector as described in Harness Connector Inspection Harness Connector Inspection.

Q. Are the wiring harness between headlight assembly (LH) connector A-37 (terminal No.
3), side turn-signal light (LH) connector A-10 (terminal No. 2) [fender type], door mirror assembly (LH) connector E-29 (terminal No. 2) [door mirror type], rear combination light
(LH) connector D-14 (terminal No. 3) and ETACS-ECU connector C-304 (terminal No. 9), ETACS-ECU connector C-311 (terminal No. 18) or ETACS-ECU connector C-317 (terminal No. 4) in good condition?

YES Go to Step 7.
NO Repair the wiring harness.
STEP 7. Using scan tool MB991958, Check whether the diagnostic trouble code is reset.





(1)
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.

Connect scan tool MB991958. Refer to "How to connect scan tool Reading and Clearing Diagnostic Trouble Codes."
(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 whether the ETACS-ECU DTC is set.

Q. Is the DTC set?

YES Replace the ETACS-ECU.

NO The procedure is complete.