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Home >> Dodge and Ram >> 2008 >> Nitro SLT, 4WD >> Repair and Diagnosis >> Engine Performance >> System >> DTCS P2314 To U1418, System Checks, O2 Sensor Check, Checking Pcm Power And Ground Circuits, Engine Cranks But No Start >> U1403-Implausible Fuel Level Signal Received >> Diagnostic Test
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Diagnostic Test

  1. ACTIVE DTC 

    Ignition on, engine not running.

    With a scan tool, select View DTCs.

    Is the DTC Active at this time? 

    Yes 

    1. Go To  2.

    No 

    1. Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
  2. CAN C BUS DTCS ALSO ACTIVE 

    With a scan tool check for DTCs in the TIPM.

    Are any CAN C related DTCs Active at this time? 

    Yes 

    1. Refer to DIAGNOSIS AND TESTING for the appropriate diagnostic procedures.
    2. Perform BODY VERIFICATION TEST - VER 1 .

    No 

    1. Go To  3.
  3. FUEL LEVEL SENSOR 
    Fig 1: Checking Fuel Level Sensor
    GC0002889Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Fuel Pump Module harness connector.

    Ignition on, engine not running.

    Using a fused jumper wire, jump the (K91) Sensor Ground circuit to the (N4) Fuel Level Sensor No.1 Signal circuit in the Fuel Pump Motor harness connector.

    Did the Fuel gauge level change from empty to full? 

    Yes 

    1. Replace the Fuel Level Sensor.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To  4.
  4. (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 2: Checking Fuel Level Sensor Signal Circuit For Short To Ground
    GC0011585Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the C7 TIPM harness connector.

    Measure the resistance between ground and the (N4) Fuel Level Signal circuit in the Fuel Pump Module harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the short to ground in the (N4) Fuel Level Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To  5.
  5. (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO THE (K91) SENSOR GROUND CIRCUIT 
    Fig 3: Checking Fuel Level Sensor Signal Circuit & Ground Circuit
    GC0002887Courtesy of CHRYSLER LLC

    Measure the resistance between the (N4) Fuel Level Signal circuit and the (K91) Sensor Ground circuit from the Fuel Pump Module harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Repair the short between the (K91) Sensor Ground circuit and the (N4) Fuel Level Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To  6.
  6. EXCESSIVE RESISTANCE IN THE (N4) FUEL LEVEL SIGNAL CIRCUIT 
    Fig 4: Measuring Resistance Of (N4) Fuel Level Signal Circuit From Fuel Pump Module Harness Connector To C7 TIPM Harness Connector
    GC0062152Courtesy of CHRYSLER LLC

    Measure the resistance of the (N4) Fuel Level Signal circuit from the Fuel Pump Module harness connector to the C7 TIPM harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To  7.

    No 

    1. Repair the excessive resistance in the (N4) Fuel Level Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  7. EXCESSIVE RESISTANCE IN THE (K91) SENSOR GROUND CIRCUIT 
    Fig 5: Measuring Resistance Of (K91) Sensor Ground Circuit From Fuel Pump Module Harness Connector To TIPM Harness Connector
    GC0062153Courtesy of CHRYSLER LLC

    Disconnect the C1 TIPM harness connector.

    Measure the resistance of the (K91) Sensor Ground circuit from the Fuel Pump Module harness connector to the TIPM harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To  8.

    No 

    1. Repair the excessive resistance in the (K91) Sensor Ground circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  8. POWERTRAIN CONTROL MODULE (PCM) 

    Using the wiring diagram/schematic as a guide, inspect the wiring and connector at the Powertrain Control Module (PCM).

    Look for any chafed, pierced, pinched, or partially broken wires.

    Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Powertrain Control Module connectors.

    Refer to any Technical Service Bulletins that may apply.

    Were there any problems found? 

    Yes 

    1. Repair as necessary.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Replace and program the Powertrain Control Module per Service Information.
    2. Perform POWERTRAIN VERIFICATION TEST .
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