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DTC P0480

DTC P0480:  Radiator Fan Control (RFC) System Malfunction

General Description 

GHH343998Courtesy of HONDA, U.S.A., INC.

The radiator fan control (RFC) system improves the control of the radiator fan motor and the condenser fan motor while decreasing noise and vibration. The powertrain control module (PCM) detects a malfunction when the FAN CONTROL terminal voltage remains at 0 V. However, the RFC power is shut off temporarily when a malfunction is detected to differentiate it from the RFC protection function* (power reset). When the FAN CONTROL terminal voltage remains at 0 V even when the power reset is repeated for set time, the PCM detects a malfunction of the RFC and stores a DTC.

*: When excessively high current due to a locked fan motor, etc. is detected or at abnormally high temperatures, fan motor operation is limited to protect the RFC unit and keep the FAN CONTROL terminal voltage at 0 V. When the problem is cleared by turning off the power once and turning it on again, the RFC protection function is canceled.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status 

Execution Continuous
Sequence None
Duration 105 seconds or more
DTC Type Two drive cycles, MIL off
OBD Status PASSED/FAILED/NOT COMPLETED (STILL TESTING)

Enable Conditions 

Condition Minimum Maximum
Battery voltage [BATTERY] 10.5 V -
Ignition switch or Engine start/stop button Vehicle ON mode

[ ]: HDS Parameter

Malfunction Threshold 

The FAN CONTROL terminal voltage is low for at least 20 seconds, and the same condition continues even when the power reset is repeated 5 times. (Power is supplied at intervals of 5 seconds after the power reset.)

Possible Cause 

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

Diagnosis Details 

Conditions for setting the DTC 

When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, a Confirmed DTC and the freeze data are stored. The MIL does not come on.

Conditions for clearing the DTC 

The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.