DTC B1201: Defective fuel gauge: 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
• MB991223: Harness Set
• MB992006: Extra Fine Probe

1. STEP 1. Using scan tool MB991958, read the MFI system diagnostic trouble code. 

   Check if an MFI system diagnostic trouble code is set.

   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 "ON" position.
   3. Read the diagnostic trouble code.
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Have any MFI system DTCs set? 

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

   NO:  Go to Step  2.

   Fig 1: Connecting Scan Tool To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. STEP 2. Using scan tool MB991958, check data list. 
   1. Start the engine.
   2. Set scan tool MB991958 to the data reading mode.
      • Item 06: fuel gauge (Input).
        • Fuel gauge unit resistance value and M.U.T.-III displayed value agree with each other.
      • Item 07: fuel gauge (Target).
        • Fuel gauge and M.U.T.-III displayed values agree with each other.
   3. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the check result normal? 

   YES:  Go to Step  18.

   NO:  Go to Step  3.

   Fig 2: Connecting Scan Tool To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. STEP 3. Check fuel level sensor (sub) connector D-10 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is fuel level sensor (sub) connector D-10 in good condition? 

   YES:  Go to Step  4.

   NO:  Repair or replace the damaged component(s). Refer to HARNESS CONNECTOR INSPECTION . The combination meter works normally.

   Fig 3: Locating Fuel Level Sensor Connector D-10 (Eclipse)

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
   Fig 4: Locating Fuel Level Sensor Connector D-10 (Eclipse Spyder)

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4. STEP 4. Check the fuel level sensor (sub). 

   Check to see if the fuel level sensor (sub) is normal. Refer to FUEL LEVEL SENSOR CHECK .

   Q: Is the fuel level sensor (sub) normal? 

   YES:  Go to Step  5.

   NO:  Replace the fuel level sensor (Refer to FUEL TANK ).

5. STEP 5. Check fuel pump module connector D-19 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is fuel pump module connector D-19 in good condition? 

   YES:  Go to Step  6.

   NO:  Repair or replace the damaged component(s). Refer to HARNESS CONNECTOR INSPECTION . Verify that the combination meter works normally.

   Fig 5: Locating Fuel Pump Module Connector D-19 (Eclipse)

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
   Fig 6: Locating Fuel Pump Module Connector D-19 (Eclipse Spyder)

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
6. STEP 6. Check the fuel pump module. 

   Check to see if the fuel pump module is normal. Refer to FUEL LEVEL SENSOR CHECK .

   Q: Is the fuel pump module normal? 

   YES:  Go to Step  7.

   NO:  Replace the fuel pump module (Refer to FUEL TANK ). The fuel gauge should now operate normally.

7. STEP 7. Check the ground circuit to the fuel pump module. Measure the resistance at fuel pump module connector D-19. 
   1. Disconnect fuel pump module connector D-19 and measure the resistance available at the harness side of the connector.
      Fig 7: Locating Fuel Pump Module Connector D-19 (Eclipse)

      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
      Fig 8: Locating Fuel Pump Module Connector D-19 (Eclipse Spyder)

      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
   2. Measure the resistance value between terminal 1 and ground.
      • The resistance should be 2 ohms or less.

   Q: Is the measured resistance 2 ohms or less? 

   YES:  Go to Step  9.

   NO:  Go to Step  8.

   Fig 9: Measuring Resistance Value Between Terminal 1 And Ground

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
8. STEP 8. Check the wiring harness between fuel pump module connector D-19 (terminal 1) and ground. 

   Q: Is the wiring harness between fuel pump module connector D-19 (terminal 1) and ground in good condition? 

   YES:  An intermittent malfunction is suspected. Refer to "How to Use Troubleshooting/inspection Service Points - HOW TO COPE WITH INTERMITTENT MALFUNCTIONS " .

   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. Verify that the combination meter works normally.

   Fig 10: Locating Fuel Pump Module Connector D-19 (Eclipse)

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
   Fig 11: Locating Fuel Pump Module Connector D-19 (Eclipse Spyder)

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
9. STEP 9. Check the wiring harness between fuel level sensor (sub) connector D-10 (terminal 1) and fuel pump module connector D-19 (terminal 2). 
   1. Disconnect fuel level sensor (sub) connector D-10 and fuel pump module connector D-19, and measure the resistance at the wiring harness side.
      Fig 12: Locating Fuel Level Sensor Connector D-10 And Fuel Pump Module Connector D-19 (Eclipse)

      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
      Fig 13: Locating Fuel Level Sensor Connector D-10 And Fuel Pump Module Connector D-19 (Eclipse Spyder)

      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
   2. Measure the resistance between fuel level sensor (sub) connector D-10 terminal 1 and fuel pump module connector D-19 terminal 2.
      • The resistance should be 2 ohms or less.

   Q: Is the measured resistance 2 ohms or less? 

   YES:  Go to Step  10.

   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. Verify that the combination meter works normally.

   Fig 14: Measuring Resistance Between Fuel Level Sensor Connector Terminal 1 And Fuel Pump Module Connector Terminal 2

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
10. STEP 10. Check combination meter connector C-04 and ECM < M/T> or PCM < A/T> connector B-19 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

    Q: Are combination meter connector C-04 and ECM < M/T> or PCM < A/T> connector B-19 in good condition? 

    YES:  Go to Step  11.

    NO:  Repair or replace the damaged component(s). Refer to HARNESS CONNECTOR INSPECTION . Verify that the combination meter works normally.

    Fig 15: Identifying Connector B-19 Terminals

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 16: Identifying Connector C-04 Terminals

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11. STEP 11. Check the wiring harness between combination meter connector C-04 (terminal 16) and fuel level sensor (sub) connector D-10 (terminal 2). 
    Fig 17: Identifying Connector C-04 Terminals

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 18: Locating Fuel Level Sensor Connector D-10 (Eclipse)

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 19: Locating Fuel Level Sensor Connector D-10 (Eclipse Spyder)

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    NOTE: Also check intermediate connector C-23 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-23 is damaged, repair or replace the damaged component(s) as described in HARNESS CONNECTOR INSPECTION .
    1. Disconnect combination meter connector C-04 and fuel level sensor (sub) connector D-10, and measure the resistance at the wiring harness side.
       Fig 20: Identifying Connector C-23 Terminals

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Measure the resistance between combination meter connector C-04 terminal 16 and fuel level sensor (sub) connector D-10 terminal 2.
       • The resistance should be 2 ohms or less.

    Q: Is the measured resistance 2 ohms or less? 

    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. Verify that the combination meter works normally.

    Fig 21: Measuring Resistance Between Combination Meter Connector Terminal 16 And Fuel Level Sensor Connector Terminal 2

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
12. STEP 12. Check the wiring harness between combination meter and the fuel level sensor (sub) for short to ground. Measure the resistance at combination meter connector C-04. 
    1. Disconnect combination meter connector C-04 and fuel level sensor (sub) connector D-10, and measure the resistance available at the harness side of the combination meter connector C-04.
       Fig 22: Identifying Connector C-04 Terminals

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
       Fig 23: Locating Fuel Level Sensor Connector D-10 (Eclipse)

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
       Fig 24: Locating Fuel Level Sensor Connector D-10 (Eclipse Spyder)

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Measure the resistance value between terminal 16 and ground.
       • The resistance should be 1 kΩ or more.

    Q: Is the measured resistance 1 kΩ or more? 

    YES:  Go to Step  14.

    NO:  Go to Step  13.

    Fig 25: Measuring Resistance Value Between Terminal 16 And Ground

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
13. STEP 13. Check the wiring harness between combination meter connector C-04 (terminal 16) and fuel level sensor (sub) connector D-10 (terminal 2). 
    Fig 26: Identifying Connector C-04 Terminals

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 27: Locating Fuel Level Sensor Connector D-10 (Eclipse)

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 28: Locating Fuel Level Sensor Connector D-10 (Eclipse Spyder)

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    NOTE: Also check intermediate connector C-23 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-23 is damaged, repair or replace the damaged component(s) as described in HARNESS CONNECTOR INSPECTION .

    Q: Is the wiring harness between combination meter connector C-04 (terminal 16) and fuel level sensor (sub) connector D-10 (terminal 2) in good condition? 

    YES:  An intermittent malfunction is suspected. Refer to "How to Use Troubleshooting/inspection Service Points - HOW TO COPE WITH INTERMITTENT MALFUNCTIONS " .

    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. Verify that the combination meter works normally.

    Fig 29: Identifying Connector C-23 Terminals

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
14. STEP 14. Check the wiring harness between fuel level sensor (sub), the fuel pump module and the ECM < M/T> or PCM < A/T> for short to ground. Measure the resistance at fuel level sensor (sub) connector D-10. 
    1. Disconnect fuel level sensor (sub) connector D-10, fuel pump module connector D-19 and ECM < M/T> or PCM < A/T> connector B-19, and measure the resistance available at the harness side of the fuel level sensor (sub) connector D-10.
       Fig 30: Identifying Connector B-19 Terminals

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
       Fig 31: Locating Fuel Level Sensor Connector D-10 And Fuel Pump Module Connector D-19 (Eclipse)

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
       Fig 32: Locating Fuel Level Sensor Connector D-10 And Fuel Pump Module Connector D-19 (Eclipse Spyder)

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Measure the resistance value between terminal 1 and ground.
       • The resistance should be 1 kΩ or more.

    Q: Is the measured resistance 1 kΩ or more? 

    YES:  Go to Step  17.

    NO:  Go to Step  15.

    Fig 33: Measuring Resistance Value Between Terminal 1 And Ground

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
15. STEP 15. Check the wiring harness between fuel level sensor (sub) connector D-10 (terminal 1) and fuel pump module connector D-19 (terminal 2). 

    Q: Is the wiring harness between fuel level sensor connector D-10 (terminal 1) and fuel pump module connector D-19 (terminal 2) in good condition? 

    YES:  Go to Step  16.

    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. Verify that the combination meter works normally.

    Fig 34: Locating Fuel Level Sensor Connector D-10 And Fuel Pump Module Connector D-19 (Eclipse)

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 35: Locating Fuel Level Sensor Connector D-10 And Fuel Pump Module Connector D-19 (Eclipse Spyder)

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
16. STEP 16. Check the wiring harness between fuel level sensor (sub) connector D-10 (terminal 1) and ECM < M/T> or PCM < A/T> connector B-19 (terminal 24). 
    Fig 36: Identifying Connector B-19 Terminals

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 37: Locating Fuel Level Sensor Connector D-10 (Eclipse)

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 38: Locating Fuel Level Sensor Connector D-10 (Eclipse Spyder)

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    NOTE: Also check intermediate connector C-26 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-26 is damaged, repair or replace the damaged component(s) as described in HARNESS CONNECTOR INSPECTION .

    Q: Is the wiring harness between fuel level sensor connector D-10 (terminal 1) and ECM < M/T> or PCM < A/T> connector B-19 (terminal 24) in good condition? 

    YES:  Go to Step  17.

    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. Verify that the combination meter works normally.

    Fig 39: Identifying C-26 Connector Terminals

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
17. STEP 17. Recheck the diagnostic trouble code. 

    Replace the combination meter, and then check that the diagnostic trouble code is not reset.

    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. Erase the diagnostic trouble code.
    4. Turn the ignition switch to the "LOCK" (OFF) position.
    5. Turn the ignition switch to "ON" position.
    6. Check if the diagnostic trouble code is set.
    7. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the check result normal? 

    YES:  The procedure is complete.

    NO:  Replace ECM < M/T> or PCM < A/T>. When the ECM < M/T> or PCM < A/T> is replaced, register the encrypted code. Refer to HOW TO REGISTER SECRET CODE .

    Fig 40: Connecting Scan Tool To Data Link Connector

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18. STEP 18. Recheck for diagnostic trouble code. 

    Recheck if the diagnostic trouble code is set.

    1. Turn the ignition switch to "ON" position.
    2. Erase the diagnostic trouble code.
    3. Turn the ignition switch to the "LOCK" (OFF) position.
    4. Turn the ignition switch to "ON" position.
    5. Check if the diagnostic trouble code is set.
    6. Turn the ignition switch to the "LOCK" (OFF) position.

    Q: Is the check result satisfactory? 

    YES:  The procedure is complete.

    NO:  Replace combination meter.

    Fig 41: Connecting Scan Tool To Data Link Connector

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.