Inspection Procedure 13: The Turn-Signal Indicator Light Do Not Illuminate: 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)

1. STEP 1. Check turn-signal light. 

   Check that the turn-signal light flashes normally when the turn-signal switch is operated.

   Q: Do Turn-signal light work normally? 

   YES  : Go to Step 2.

   NO  : Refer to INSPECTION PROCEDURE 11 "THE TURN-SIGNAL LIGHTS DO NOT ILLUMINATE"  .

2. STEP 2. Using scan tool MB991958, diagnose the CAN bus line. 
   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. Diagnose the CAN bus line.
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the CAN bus line found to be normal? 

   YES  : Go to Step 3.

   NO  : Repair the CAN bus line (Refer to DIAGNOSIS ).

   Fig 1: Connecting Special Tool To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. STEP 3. Using scan tool MB991958, read the diagnostic trouble code. 

   Check if diagnostic trouble code is set to the ETACS-ECU.

   1. Turn the ignition switch to the "ON" position.
   2. Check whether the ETACS-ECU related DTC is set.
   3. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the DTC set? 

   YES  : Diagnose the ETACS-ECU. Refer to DIAGNOSTIC TROUBLE CODE CHART .

   NO  : Go to Step 4.

4. STEP 4. Using scan tool MB991958, check actuator test. 
   1. Connect scan tool MB991958 to the data link connector.
   2. Turn the ignition switch to the "ON" position.
   3. Set scan tool MB991958 to the actuator test mode.
      • Item 7: Indicator1
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the check result normal? 

   YES  : Replace the ETACS-ECU.

   NO  : Replace the combination meter.