* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Special Tools
J 33431-C Instrument Panel Tester
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the fuel level sensor.
2. Ignition OFF, test for less than 1 ohm between the low reference circuit terminal B and ground.
锟斤拷If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
3. Install a Signal Generator and Instrument Panel Tester between the signal circuit terminal C and the low reference circuit terminal B.
4. Ignition ON, vary the signal generator resistance between 40 and 250 ohm. Verify that the scan tool Fuel Tank Level Remaining parameter
displays a range that varies between 5 and 95 percent as the signal generator resistance changes.
锟斤拷If not within the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
5. If all circuits test normal, perform the fuel level sensor component test before replacing the fuel level sensor.
Component Testing
1. Ignition OFF, disconnect the harness connectors at the fuel level sensor.
2. While sweeping the fuel level sensor through its full range of motion, test for a minimum value less than 41 ohm and a maximum value
greater than 119 ohm between the signal terminal C and the low reference terminal B.
锟斤拷If not within the specified range, replace the fuel level sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Fuel Level Sensor Replacement (See: Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and Repair) for
the 6.0L (LFA) engine
* Fuel Level Sensor Replacement (2500 - 98.4L (26 gal) Tank - Front) (See: Powertrain Management/Computers and Control Systems/Fuel
Level Sensor/Service and Repair/Fuel Level Sensor Replacement (2500 - 98.4L (26 Gal) Tank - Front))Fuel Level Sensor Replacement
(2500 - 43.5L (11.5 gal) Tank - Rear) (See: Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and
Repair/Fuel Level Sensor Replacement (2500 - 43.5L (11.5 Gal) Tank - Rear))Fuel Level Sensor Replacement (1500 Series) (See:
Powertrain Management/Computers and Control Systems/Fuel Level Sensor/Service and Repair/Fuel Level Sensor Replacement (1500
Series))Fuel Level Sensor Replacement (1500 Series w/E85) (See: Powertrain Management/Computers and Control Systems/Fuel Level
Sensor/Service and Repair/Fuel Level Sensor Replacement (1500 Series w/E85)) for the 4.8L, 5.3L, 6.0L, 6.2L, or 7.0L engine
* Control Module References (See: Testing and Inspection/Programming and Relearning) for ECM replacement, programming and setup
P0480
DTC P0480 or P0481 (without HP2)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0480
- Cooling Fan Relay 1 Control Circuit
