Inspection Procedure 1: None of taillights illuminates: Diagnosis

WARNING: This page is about a different variant/trim than selected.

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. License plate light operation check
Check that the license plate light illuminates normally.

Q: Does license plate light work normally?
- YES: Go to Step 2.
- NO: Replace the ETACS-ECU.
STEP 2. Using scan tool MB991958, read the diagnostic trouble code.
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 (M.U.T.-III) ."
2. Turn the ignition switch to the "ON" position.
3. Check whether the ETACS-ECU related DTC is set.
4. Turn the ignition switch to the "LOCK" (OFF) position.
  Q: Is the DTC set?
  - YES: Diagnose the ETACS-ECU. Refer to DIAGNOSIS .
  - NO: Go to Step 3.
    
    Fig 1: Connecting Special Tool MB991910 To Data Link Connector
    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

STEP 3. Using scan tool MB991958, check data list.

Use the ETACS-ECU data list to check the signals related to the taillight illumination.

Turn the ignition switch to the "ACC" position.

Turn the taillight switch to the "ON" position.

ITEM REFERENCE CHART

Item No.	Item name	Normal conditions
Item 218	Taillight	ON

Q: Does scan tool MB991958 display the items "Taillight" as normal condition?

YES: Go to Step 4.
NO: Troubleshoot the ETACS-ECU (Refer to TROUBLE SYMPTOM CHART FOR INPUT SIGNAL ).

STEP 4. Retest the system
Check that the taillight illuminates normally.

Q: Does the taillight work normally?
- YES: The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
- NO: Replace the ETACS-ECU.