INSPECTION PROCEDURE 8: Tachometer does not work (other meters work): Diagnosis

Required Special Tools: 

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)
  • MB991824: V.C.I.
  • MB991827: M.U.T.-III USB Cable
  • MB991910: M.U.T.-III Main Harness A

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 to the data link connector.
   2. Turn the ignition switch to "ON" position.
   3. Diagnose the CAN bus line.
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the check result satisfactory? 

   YES:  Go to Step  2.

   NO:  Repair the CAN bus lines (Refer to CAN BUS DIAGNOSTIC CHART ).

   Fig 1: Connecting Scan Tool To Data Link Connector

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2. STEP 2. Using scan tool MB991958, read MFI system diagnostic trouble code. 

   Check if the MFI system diagnostic trouble code is set.

   1. Turn the ignition switch to "ON" position.
   2. Diagnose the CAN bus line.
   3. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the DTC set? 

   YES:  Refer to DIAGNOSTIC TROUBLE CODE CHART for 2.4L or DIAGNOSTIC TROUBLE CODE CHART for 3.8L.

   NO:  Go to Step  3.

   Fig 2: Connecting Scan Tool To Data Link Connector

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3. STEP 3. Using scan tool MB991958, check data list. 
   1. Turn the ignition switch to the "ON" position.
   2. Set scan tool MB991958 to the data reading mode.
      • Item 05: Tachometer
        • Tachometer displayed value and M.U.T.-III displayed value agree with each other.
   3. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the check result normally? 

   YES:  It can be assumed that this malfunction is intermittent. Refer to "How to Use Troubleshooting/inspection Service Points - HOW TO COPE WITH INTERMITTENT MALFUNCTIONS " .

   NO:  Go to Step  4.

   Fig 3: Connecting Scan Tool To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
4. STEP 4. Using scan tool MB991958, check actuator test. 
   1. Turn the ignition switch to the "ON" position.
   2. Set scan tool MB991958 to the actuator test mode.
      • Item 4: Tachometer: 0 r/min
        • The tachometer displays 0 r/min..
      • Item 5: Tachometer: 2,000 r/min
        • The tachometer displays 2,000 r/min.
      • Item 6: Tachometer: 5,000 r/min
        • The tachometer displays 5,000 r/min.
   3. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the check result normally? 

   YES:  Go to Step  5.

   NO:  Replace the combination meter.

   Fig 4: Connecting Scan Tool To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
5. STEP 5. Retest the system. 

   Check that the tachometer works normally.

   Q: Is the check result satisfactory? 

   YES:  The procedure is complete. (If no malfunctions are found in all steps, an intermittent malfunction is suspected. Refer to "How to Use Troubleshooting/inspection Service Points - HOW TO COPE WITH INTERMITTENT MALFUNCTIONS " ).

   NO:  Replace the combination meter.