B16A7

DTC B16A7: Taillight
(RH) circuit short [Short circuit in the position light (RH) circuit, the taillight (RH) circuit or the rear side marker light (RH) circuit]

[LANCER]

[LANCER SPORTBACK]

TROUBLE JUDGMENT

When a short circuit is detected in the position lamp circuit or the tail lamp circuit, the ETACS-ECU sets the diagnosis code No. B16A7.

TECHNICAL DESCRIPTION (COMMENT)

The problem detection of tail lamp is made based on the digital feed back signal (input signal to ETACS-ECU) which operates the tail lamp. When the ignition switch is ON, the ETACS-ECU determines the tail lamp 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 diagnosis code No. B16A7 if no load is detected.

TROUBLESHOOTING HINTS

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

- Malfunction of bulbs

- 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(s) of the light that does not illuminate.

Q. Is the check result normal?

YES [LANCER] : Go to Step 2.
YES [LANCER SPORTBACK] : Go to Step 7.
NO : Replace the bulb(s) of the light that does not illuminate.
STEP 2. Check headlight assembly (position light: RH) connector A-47, rear combination light (taillight/side marker light: RH) connector F-06 and taillight (RH) connector F-07 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is headlight assembly (position light: RH) connector A-47, rear combination light
(taillight/side marker light: RH) connector F-06 and taillight (RH) connector F-07 in good condition?

YES Go to Step 3.
NO : Repair or replace the damaged component(s). Harness Connector Inspection.
STEP 3. Resistance measurement at headlight assembly (position light: RH) connector A-47, rear combination light (taillight/side marker light: RH) connector F-06 and taillight (RH) connector F-07.

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

- Check the wiring harness between headlight assembly (position light: RH) connector A-47
(terminal 6) and the body ground.

- Check the wiring harness between rear combination light (taillight/side marker light: RH) connector F-06 (terminal 1) and the body ground.

- Check the wiring harness between taillight (RH) connector F-07 (terminal 1) and the body ground.
NOTE:
Also check intermediate connector F-23 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector F-23 is damaged, repair or replace the connector as described in Harness Connector Inspection Harness Connector Inspection.

Q. Is the wiring harness between headlight assembly connector, rear combination light connector or tail light connector and the body ground in good condition?

YES Go to Step 12.

NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.

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. Is ETACS-ECU connector C-304 or C-311 in good condition?

YES Go to Step 6.
NO Repair or replace the damaged component(s). Harness Connector Inspection.
STEP 6. Check wiring harness between headlight assembly connector, rear combination light connector, taillight connector and ETACS-ECU connector.

Check the power supply line for open circuit or short circuit.

- Check the wiring harness between headlight assembly (position light: RH) connector A-47 (terminal 4) and ETACS-ECU connector C-304 (terminal 7).

- Check the wiring harness between rear combination light (taillight/side marker light: RH) connector F-06 (terminal 3) and ETACS-ECU connector C-311 (terminal 13).
NOTE:
Also check intermediate connector D-11 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector D-11 is damaged, repair or replace the connector as described in Harness Connector Inspection Harness Connector Inspection.

- Check the wiring harness between taillight (RH) connector F-07 (terminal 2) and ETACS-ECU connector C-311 (terminal 13).
NOTE:
Also check intermediate connectors D-14 and F-23 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector D-14 or F-23 is damaged, repair or replace the connector as described in Harness Connector Inspection Harness Connector Inspection.

Q. Is the wiring harness between headlight assembly connector, rear combination light connector, taillight connector and ETACS-ECU connector in good condition?

YES Go to Step 12.
NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.
STEP 7. Check headlight assembly (position light: RH) connector A-47, rear combination light (taillight: RH) connector F-06 and rear side marker light (RH) connector F-35 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is headlight assembly (position light: RH) connector A-47, rear combination light
(taillight: RH) connector F-06 and rear side marker light (RH) connector F-35 in good condition?

YES Go to Step 8.
NO : Repair or replace the damaged component(s). Harness Connector Inspection.
STEP 8. Resistance measurement at headlight assembly (position light: RH) connector A-47, rear combination light (taillight: RH) connector F-06 and rear side marker light (RH) connector F-35.

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

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

- Measure the resistance between headlight assembly (position light: RH) connector A-47
(terminal 6) and the body ground.

- Measure the resistance between rear combination light (taillight: RH) connector F-06 (terminal 3) and the body ground.

- Measure the resistance between rear side marker light (RH) connector F-35 (terminal 1) and the body ground.
OK: 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 headlight assembly connector, rear combination light connector or rear side marker light connector and the body ground.

Check the ground line for open circuit.

- Check the wiring harness between headlight assembly (position light: RH) connector A-47 (terminal 6) and the body ground.

- Check the wiring harness between rear combination light (taillight: RH) connector F-06 (terminal 3) and the body ground.

- Check the wiring harness between rear side marker light (RH) connector F-35 (terminal 1) and the body ground.

Q. Is the wiring harness between headlight assembly connector, rear combination light connector or rear side marker light connector and the body ground in good condition?

YES Go to Step 12.
NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.
STEP 10. Check ETACS-ECU connectors C-304 and C-311 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is ETACS-ECU connector C-304 or C-311 in good condition?

YES Go to Step 11.
NO Repair or replace the damaged component(s). Harness Connector Inspection.
STEP 11. Check wiring harness between headlight assembly connector, rear combination light connector, rear side marker light connector and ETACS-ECU connector.

Check the power supply line for open circuit or short circuit.

- Check the wiring harness between headlight assembly (position light: RH) connector A-47 (terminal 4) and ETACS-ECU connector C-304 (terminal 7).

- Check the wiring harness between rear combination light (taillight: RH) connector F-06 (terminal 2) and ETACS-ECU connector C-311 (terminal 13).
NOTE:
Also check intermediate connector D-11 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector D-11 is damaged, repair or replace the connector as described in Harness Connector Inspection Harness Connector Inspection.

- Check the wiring harness between rear side marker light (RH) connector F-35 (terminal 2) and ETACS-ECU connector C-311 (terminal 13).
NOTE:
Also check intermediate connector D-11 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector D-11 is damaged, repair or replace the connector as described in Harness Connector Inspection Harness Connector Inspection.

Q. Is the wiring harness between headlight assembly connector, rear combination light connector, rear side marker light connector and ETACS-ECU connector in good condition?

YES Go to Step 12.
NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.
STEP 12. 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 too (M.U.T.-III) 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 if DTC is set.

Q. Is the DTC set?

YES Replace the ETACS-ECU.

NO The procedure is complete.