P0481 2003 FORD F150 - High Fan Control Primary Circuit Failure
P0481 2003 Ford F150 Possible Causes
- Faulty fan control relay
- Faulty cooling fan 2
- Fan control relay harness is open or shorted
- Fan control relay circuit poor electrical connection
- Fan cooling fan harness is open or shorted
- Fan cooling fan circuit poor electrical connection
- Damaged PCM
P0481 2003 Ford F150 Tech NotesMonitors the high fan control (HFC) primary circuit output from the PCM. The test fails if: With the HFC output commanded on (grounded), excessive current draw is detected on the HFC circuit; or with the HFC circuit commanded off, voltage is not detected on the HFC circuit (the PCM expects to detect VPWR voltage coming through the high speed FC relay [or CCRM] coil to the HFC circuit).
Cost of diagnosing the P0481 2003 Ford F150 code
Labor: 1.0The cost of diagnosing the P0481 2003 Ford F150 code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
When is the code detected?The P0481 code is detected when the Engine Control Module (ECM) detects that the commanded state of the driver and the actual state of the control circuit do not match.
P0481 2003 Ford F150 Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Engine overheating
P0481 2003 Ford F150 MeaningThe electric cooling fan is controlled by the Engine Control Module (ECM) through the cooling fan relay based on inputs from the following components:
- The engine coolant temperature (ECT) sensor
- The intake air temperature (IAT) sensor
- The A/C selector switch
- The A/C refrigerant pressure sensor
- The vehicle speed sensor (VSS)
The ECM controls the cooling fan by grounding the cooling fan control circuit which turns ON the cooling fan relay. The cooling fan relay will be commanded ON when the following conditions are met:
- The engine coolant temperature reaches 106°C (223°F) or more.
- The A/C clutch requested.
- The vehicle speed is less than 38 MPH.
The cooling fan relay will be commanded ON regardless of vehicle speed when the following conditions are met:
- The engine coolant temperature is 151°C (304°F) or more.
- The A/C refrigerant pressure is high.
The cooling fan may be commanded ON when the engine is not running under a fan run-on conditions described in the electric cooling fan general description portion of the service manual.