B16A3

DTC B16A3: Turn-signal light (LH) short circuit

Turn-Signal Lights Circuit (LH) Part 1:

Turn-Signal Lights Circuit (LH) Part 2:

TROUBLE JUDGMENT
When the left wiring harness of turn-signal light is short circuited, the ETACS-ECU sets DTC B16A3.

TECHNICAL DESCRIPTION (COMMENT)
When the short circuit is detected three times consecutively, the ETACS-ECU sets the DTC B16A3

TROUBLESHOOTING HINTS
- 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. Check headlight assembly (LH) connector A-37 ,side turn-signal light (LH) connector A-10 ,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 , rear combination light (LH) connector D-14 in good condition?

YES: Go to Step 2.

NO: Repair the damaged parts.

STEP 2. Resistance measurement at headlight assembly (LH) connector A-37 , side turn-signal light (LH) connector A-10 , and 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. 8) and body ground.
- Measure the resistance between side turn-signal light (LH) connector A-10 (terminal No. 1) and body ground.
- 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 4.

NO: Go to Step 3.

STEP 3. Check the wiring harness between headlight assembly (LH) connector A-37 (terminal No. 8) , side turn-signal light (LH) connector A-10 (terminal No. 1) , rear combination light (LH) connector D-14 (terminal No. 4) and ground.

Q: Are the wiring harness between headlight assembly (LH) connector A-37 (terminal No. 8) , side turn-signal light (LH) connector A-10 (terminal No. 1) , rear combination light (LH) connector D-14 (terminal No. 4) and ground in good condition?

YES: Go to Step 6.

NO: Repair the wiring harness.

STEP 4. Check ETACS-ECU connectors C-304 and C-310 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Are ETACS-ECU connectors C-304 and C-310 in good condition?

YES: Go to Step 5.

NO: Repair the damaged parts.

STEP 5. Check the wiring harness between headlight assembly (LH) connector A-37 (terminal No. 5) , side turn-signal light (LH) connector A-10 (terminal No. 2) , rear combination light (LH) connector D-14 (terminal No. 3) and ETACS-ECU connector C-304 (terminal No. 9) or ETACS-ECU connector C-311 (terminal No. 18) .

Q: Are the wiring harness between headlight assembly (LH) connector A-37 (terminal No. 5) , side turn-signal light (LH) connector A-10 (terminal No. 2) , rear combination light (LH) connector D-14 (terminal No. 3) and ETACS-ECU connector C-304 (terminal No. 9) or ETACS-ECU connector C-311 (terminal No. 18) in good condition?

YES: Go to Step 6.

NO: Repair the wiring harness.

STEP 6. 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."
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.