DTC B1201: Defective fuel gauge: Diagnosis

Required Special Tools: 

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)
  • MB991824: Vehicles 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)
• 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 DTC is set.

   Q: Is the DTC set? 

   YES:  Diagnose the MFI system by referring to DIAGNOSTIC TROUBLE CODE CHART < 2.4L ENGINE > or DIAGNOSTIC TROUBLE CODE CHART < 3.8L ENGINE >.

   NO:  Go to Step 2.

2. STEP 2. Using scan tool MB991958, check data list. 
   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 the "ON" position.
   3. Set scan tool MB991958 to the actuator test mode.
      • Item 89: Fuel gauge.
        • Fuel gauge unit resistance value and M.U.T.-III displayed value agree with each other.
      • Item 8A: Fuel gauge (Target).
        • Fuel gauge and M.U.T.-III displayed values agree with each other.
   4. Turn the ignition switch to the "LOCK" (OFF) position.

   Q: Is the solenoid valve operating properly? 

   YES:  Go to Step  18.

   NO:  Go to Step 3.

   Fig 1: Connecting Scan Tool To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. STEP 3. Check fuel level sensor (sub) connector D-17 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is fuel level sensor (sub) connector D-17 in good condition? 

   YES:  Go to Step 4.

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

   Fig 2: Identifying D-17 Connector Terminals

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
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-18 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

   Q: Is fuel pump module connector D-18 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 work normally.

   Fig 3: Locating Fuel Pump Module Connector D-18

   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-18. 
   1. Disconnect fuel pump module connector D-18 and measure the resistance available at the harness side of the connector.
      Fig 4: Locating Fuel Pump Module Connector D-18

      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 8.

   NO:  Go to Step  9.

   Fig 5: 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-18 (terminal 1) and ground. 

   Q: Is the wiring harness between fuel pump module connector D-18 (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 work normally.

   Fig 6: Locating Fuel Pump Module Connector D-18

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
9. STEP 9. Check the wiring harness between fuel level sensor (sub) connector D-17 (terminal 1) and fuel pump module connector D-18 (terminal 2) 
   1. Disconnect fuel level sensor (sub) connector D-17 and fuel pump module connector D-18, and measure the resistance at the wiring harness side.
      Fig 7: Identifying Connector D-17, D-18 Terminals

      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
   2. Measure the resistance between fuel level sensor (sub) connector D-17 terminal 1 and fuel pump module connector D-18 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:  Repair the wiring harness.

   Fig 8: Measuring Resistance Between Fuel Level Sensor Terminal 1 And Fuel Pump Module Terminal 2

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
10. STEP 10. Check combination meter connector C-101 and powertrain control module connector B-20 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

    Q: Are combination meter connector C-101 and powertrain control module connector B-20 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 work normally.

    Fig 9: Identifying Connector C-101 Terminals

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 10: Locating Powertrain Control Module Connector B-20

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
11. STEP 11. Check the wiring harness between combination meter connector C-101 (terminal 13) and fuel level sensor (sub) connector D-17 (terminal 2). 
    NOTE: Also check intermediate connector C-28 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-28 is damaged, repair or replace the damaged component(s) as described in HARNESS CONNECTOR INSPECTION .
    Fig 11: Locating Intermediate Connector C-28

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    1. Disconnect combination meter connector C-101 and fuel level sensor (sub) connector D-17, and measure the resistance at the wiring harness side.
       Fig 12: Identifying Connector C-101 Terminals

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
       Fig 13: Identifying D-17 Connector Terminals

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Measure the resistance between combination meter connector C-101 terminal 13 and fuel level sensor (sub) connector D-17 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:  Repair the wiring harness.

    Fig 14: Measuring Resistance Between Combination Meter Terminal 13 And Fuel Level Sensor 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-101. 
    1. Disconnect combination meter connector C-101 and fuel level sensor (sub) connector D-17, and measure the resistance available at the harness side of the combination meter connector C-101.
       Fig 15: Identifying Connector C-101 Terminals

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
       Fig 16: Identifying D-17 Connector Terminals

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Measure the resistance value between terminal 13 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 17: Measuring Resistance Value Between Terminal 13 And Ground

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
13. STEP 13. Check the wiring harness between combination meter connector C-101 (terminal 13) and fuel level sensor (sub) connector D-17 (terminal 2). 
    NOTE: Also check intermediate connector C-28 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-28 is damaged, repair or replace the damaged component(s) as described in HARNESS CONNECTOR INSPECTION .
    Fig 18: Locating Intermediate Connector C-28

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the wiring harness between combination meter connector C-101 (terminal 13) and fuel level sensor (sub) connector D-17 (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 work normally.

    Fig 19: Identifying Connector C-101 Terminals

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 20: Identifying D-17 Connector 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 powertrain control module for short to ground. Measure the resistance at fuel level sensor (sub) connector D-17. 
    1. Disconnect fuel level sensor (sub) connector D-17, fuel pump module connector D-18 and powertrain control module connector B-20, and measure the resistance available at the harness side of the fuel level sensor (sub) connector D-17.
       Fig 21: Identifying Connector D-17, D-18 Terminals

       Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
       Fig 22: Locating Powertrain Control Module Connector B-20

       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 23: 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-17 (terminal 1) and fuel pump module connector D-18 (terminal 2). 

    Q: Is the wiring harness between fuel level sensor connector D-17 (terminal 1) and fuel pump module connector D-18 (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 work normally.

    Fig 24: Identifying Connector D-17, D-18 Terminals

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
16. STEP 16. Check the wiring harness between fuel level sensor (sub) connector D-17 (terminal 1) and powertrain control module connector B-20 (terminal 24). 
    NOTE: Also check intermediate connector C-25 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-25 is damaged, repair or replace the damaged component(s) as described in HARNESS CONNECTOR INSPECTION .
    Fig 25: Locating Intermediate Connector C-25

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the wiring harness between fuel level sensor connector D-17 (terminal 1) and powertrain control module connector B-20 (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 work normally.

    Fig 26: Identifying D-17 Connector Terminals

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 27: Locating Powertrain Control Module Connector B-20

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
17. STEP 17. Replace the combination meter, and then recheck the DTC. 

    Replace the combination meter, and then check that the DTC is not reset.

    Q: Is the check result normally? 

    YES:  The procedure is complete.

    NO:  Replace powertrain control module. When the powertrain control module is replaced, register the encrypted code. Refer to ENCRYPTED CODE REGISTRATION PROCEDURE  .

18. STEP 18. Recheck for diagnostic trouble code. 

    Recheck if the DTC is set.

    1. Erase the DTC.
    2. Turn the ignition switch to "OFF" position.
    3. Turn the ignition switch to "ON" position.
    4. Drive the vehicle and check that the diagnostic trouble code is not set.

    Q: Is the check result satisfactory? 

    YES:  The procedure is complete.

    NO:  Replace combination meter.

    Fig 28: Connecting Scan Tool To Data Link Connector

    Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.