Inspection Procedure 4: Tone Alarm Does Not Sound Normally: 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. 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 THE 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? 

      1. YES:  Go to Step 2.
      2. NO:  Repair the CAN bus line (Refer to DIAGNOSIS ).
         Fig 1: Connecting Scan Tool To Data Link Connector

         Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. STEP 2. Using scan tool MB991958, read the combination meter diagnostic trouble code. 

   Check if DTC is set to the combination meter.

   Q: Is the DTC set? 

   1. YES:  Troubleshoot the combination meter (Refer to DIAGNOSTIC TROUBLE CODE CHART  ).
   2. NO:  Go to Step 3.
3. STEP 3. Using scan tool MB991958, read for any diagnostic trouble code. 

   Check if diagnostic trouble code is set to the engine control module, TC-SST-ECU, ASC-ECU, ETACS-ECU, WCM, KOS-ECU, audio and A/C-ECU.

   Q: Is the DTC set to the any of the above? 

   1. YES <Set to the engine control module.>:  Troubleshoot the engine control module (Refer to DIAGNOSIS ).
   2. YES <Set to the TC-SST-ECU.>:  Troubleshoot the TC-SST (Refer to DIAGNOSIS ).
   3. YES <Set to the ASC-ECU.>:  Troubleshoot the ASC (Refer to DIAGNOSIS ).
   4. YES <Set to the ETACS.>:  Troubleshoot the ETACS (Refer to DIAGNOSTIC TROUBLE CODE CHART ).
   5. YES <Set to the WCM.>:  Troubleshoot the WCM (Refer to DIAGNOSIS ).
   6. YES <Set to the KOS.>:  Troubleshoot the KOS (Refer to DIAGNOSIS ).
   7. YES <Set to the audio.>:  Troubleshoot the audio (Refer to DIAGNOSTIC TROUBLE CODE CHART ).
   8. YES <Set to the A/C.>:  Troubleshoot the A/C (Refer to AUTO A/C DIAGNOSIS ).
   9. NO <The diagnostic trouble code is not set.>:  Go to Step 4.
4. STEP 4. Check by scan tool MB991958 "Special Function" 

   Using scan tool MB991958, select "Test" from the special function of the combination meter. Execute the following item to check the tone alarm.

   • Item 3: Buzzer (AUTO)

     Q: Is the check result normal? 

     1. YES:  Go to Step 5.
     2. NO:  Replace the combination meter.
5. STEP 5. Retest the system 

   Check that the tone alarm normally.

   Q: Is the check result normal? 

   1. YES:  The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
   2. NO:  Replace the combination meter.