B16A4

DTC B16A4: Blown Turn-signal Light (RH) Bulb

Turn-Signal Lights Circuit (RH):

DIAGNOSTIC FUNCTION
When the right bulb of turn-signal light is blown, the ETACS-ECU sets DTC B16A4.

TECHNICAL DESCRIPTION (COMMENT)
The ETACS-ECU sets DTC B16A4 under the following conditions.
- If there is a malfunction to the right turn-signal light bulb, the blown right bulb counter counts once when the illumination of hazard or turn-signal light (right side) is attempted.
- If the blown right bulb counter reaches "3," the DTC B16A4 is set.

TROUBLESHOOTING HINTS
- Malfunction of turn-signal light bulb (right side)
- 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 bulb of turn-signal light which does not illuminate is normal.

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 (RH) connector A-56 [front], side turn-signal light (RH) connector A-60 [side], rear combination light (RH) connector D-09 [rear] for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Are headlight assembly (RH) connector A-56 [front], side turn-signal light (RH) connector A-60 [side], rear combination light (RH) connector D-09 [rear] in good condition?

YES : Go to Step 3.

NO : Repair the damaged parts.

STEP 3. Resistance measurement at headlight assembly (RH) connector A-56 [front], side turn-signal light (RH) connector A-60 [side], and rear combination light (RH) connector D-09 [rear].

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 body ground.




- Measure the resistance between the headlight assembly (RH) connector A-56 (terminal No. 8) and body ground. [Front]





- Measure the resistance between the side turn-signal light (RH) connector A-60 (terminal No. 1) and body ground. [side]





- Measure the resistance between the rear combination light (RH) connector D-09 (terminal No. 4) and body ground. [Rear]
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 (RH) connector A-56 (terminal No. 8) [front], side turn-signal light (RH) connector A-60 (terminal No. 1) [side], rear combination light (LH) connector D-09 (terminal No. 4) [rear] and ground.

Q: Are the wiring harness between headlight assembly (RH) connector A-56 (terminal No. 8) [front], side turn-signal light (RH) connector A-60 (terminal No. 1) [side], rear combination light (RH) connector D-09 (terminal No. 4) [rear] and ground in good condition?

YES : Go to Step 7.

NO : Repair the wiring harness.

STEP 5. Check ETACS-ECU connectors C-304 and C-311 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Are ETACS-ECU connectors C-304 and C-311 in good condition?

YES : Go to Step 6.

NO : Repair the damaged parts.

STEP 6. Check the wiring harness between headlight assembly (RH) connector A-56 (terminal No. 5) [front], side turn-signal light (RH) connector A-60 (terminal No. 2) [side], rear combination light (RH) connector D-09 (terminal No. 3) [rear] and ETACS-ECU connector C-304 (terminal No. 16) [front or side] or ETACS-ECU connector C-311 (terminal No. 19) [rear].

Q: Are the wiring harness between headlight assembly (RH) connector A-56 (terminal No. 5) [front], side turn-signal light (RH) connector A-60 (terminal No. 2) [side], rear combination light (RH) connector D-09 (terminal No. 3) [rear] and ETACS-ECU connector C-304 (terminal No. 16) [front or side] or ETACS-ECU connector C-311 (terminal No. 19) [rear] 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.

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 : Replace the ETACS-ECU.

NO : The procedure is complete.