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Home >> Jeep >> 2020 >> Gladiator Altitude, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> 3.6L - DTCS U110C To U1504 >> DTC Troubleshooting >> U1403-Implausible Fuel Level Signal Received >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. Turn the ignition on.
    2. With the scan tool, read DTCs and record on the repair order.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. VERIFY THAT THE BODY CONTROL MODULE IS CAPABLE OF SETTING FUEL LEVEL SENSOR FAULTS 
    1. Check the BCM fault code list to verify that the BCM has the capability to set DTCs against the Fuel Level Sensor. Refer to DIAGNOSTIC CODE INDEX .

      Are there any Fuel Level Sensor faults listed in the DTC list for the BCM?

      Yes 

      • Go To  3

      No 

      • Go To  4
  3. CHECK THE BODY CONTROL MODULE FOR FUEL LEVEL SENSOR FAULTS 
    1. With the scan tool, read DTCs in the BCM.

      Is the BCM setting any DTCs against the Fuel Level Sensor?

      Yes 

      No 

  4. CHECK THE FUEL LEVEL SENSOR WIRING 
    1. Turn the ignition off.
    2. Disconnect the Fuel Level Sensor harness connector.
    3. Disconnect the appropriate BCM harness connector.
    4. Check the Fuel Level Sensor wires:
      • for an open condition.
      • for a short to voltage.
      • for a short to ground.
      • for a short to each other.

      Were any problems found with the wiring?

      Yes 

      No 

      • Go To  5
  5. FUEL LEVEL SENSOR 
    1. Replace the Fuel Level Sensor in accordance with the Service Information.
    2. Reconnect all harness connectors.
    3. Turn the ignition on.
    4. With the scan tool, read DTCs and record on the repair order.

      Is the DTC still active?

      Yes 

      No