Diagnostic Test

ACTIVE DTC
NOTE:
Diagnose and repair any CAN BUS, communication or implausible signal DTCs before proceeding with this test.

NOTE:
Diagnose P0462 or P0463 first, if set along with P0461.
1. Start the engine.
2. Allow the engine to reach normal operating temperature.
3. With the scan tool, select View DTCs.
  NOTE:
  It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.
  
  Is the DTC Active or Pending at this time?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK FOR COMMUNICATION DTCS PRESENT
Are the U110F or U1411 DTCs present in the PCM?

Yes
- Diagnose and repair those DTCs.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 3
FUEL LEVEL SENSOR CIRCUIT DTCS SET IN THE BCM
Are any Fuel Level Sensor Circuit DTCs set in the BCM?

Yes
- Diagnose the appropriate Fuel Level Sensor Circuit DTC in the BCM. Refer to DIAGNOSTIC CODE INDEX .
No
- Go To 4
VISUALLY INSPECT FUEL TANK
1. Visually inspect the Fuel Tank for damage that may restrict the Fuel Sending Unit float from moving.
  Is the Fuel Tank OK?
  
  Yes
  - Go To 5
  No
  - Replace the Fuel Tank as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK FOR HIGH RESISTANCE IN THE (N4) FUEL LEVEL SIGNAL 1 CIRCUIT
1. Disconnect the Fuel Tank Assembly in-line harness connector.
2. Disconnect the BCM E harness connector.
3. Measure the resistance of the (N4) Fuel Level Signal 1 circuit between the Fuel Tank Assembly in-line harness connector and the BCM E harness connector.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Go To 6
  No
  - Repair the (N4) Fuel Level Signal 1 circuit for an open or high resistance.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK FOR HIGH RESISTANCE IN THE (G109) FUEL LEVEL SENSE RETURN CIRCUIT
1. Measure the resistance of the (G109) Fuel Level Signal Sense Return circuit between the Fuel Tank Assembly in-line harness connector and the BCM E harness connector.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Go To 7
  No
  - Repair the (G109) Fuel Level Signal Sense Return circuit for an open or high resistance.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
INTERNAL INSPECTION OF THE FUEL TANK
WARNING:
The fuel system is under a constant pressure (even with the engine off). Before testing or servicing any fuel system hose, fitting or line, the fuel system pressure must be released. Failure to follow these instructions can result in possible serious or fatal injury.
1. Remove the Fuel Tank in accordance with the service information. Refer to TANK, FUEL, REMOVAL .
2. Visually inspect the Fuel Tank Assembly harness for any signs of damage which could cause an open or shorted circuit.
3. Remove the Fuel Pump Module. Refer to MODULE, FUEL PUMP, REMOVAL .
4. Visually inspect the inside of the Fuel Tank for any obstructions or deformities.
5. Inspect the Fuel Pump Module Float arm for damage.
  Were any problems found?
  
  Yes
  - Perform the necessary repairs.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 8
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Body Control Module (BCM) and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Sensor and Powertrain Control Module connectors.
4. Perform any Technical Service Bulletins that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Replace and program the Powertrain Control Module in accordance with the service information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .