AutoCodes – Ford – P1477 Ford

P1477 Ford Code - Medium Cooling Fan Control Primary Circuit Failure

Quick Answer

Monitors the medium fan control (MFC) primary circuit output from the Powertrain Control Module (PCM). Common causes include Faulty Cooling Fan Relay, Cooling Fan Relay harness is open or shorted, Cooling Fan Relay circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1477 Ford indicates Medium Cooling Fan Control Primary Circuit Failure.
Common causes: Common causes include Faulty Cooling Fan Relay, Cooling Fan Relay harness is open or shorted, Cooling Fan Relay circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 8,864

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Aug 24, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
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Code P1477 Ford Description

Monitors the medium fan control (MFC) primary circuit output from the Powertrain Control Module (PCM). The test fails if: With the MFC output commanded on (grounded), excessive current draw is detected on the MFC circuit; or with the MFC circuit commanded off, voltage is not detected on the MFC circuit (the PCM expects to detect IGN START/RUN voltage coming through the medium speed FC relay coil to the MFC circuit).

OBDII Code P1477 Ford - Medium Cooling Fan Control Primary Circuit Failure - AutoCodes.com — P1477 Ford Code - Medium Cooling Fan Control Primary Circuit Failure

What does this mean?

What are the Possible Causes of the DTC P1477 Ford?

Faulty Cooling Fan Relay
Cooling Fan Relay harness is open or shorted
Cooling Fan Relay circuit poor electrical connection
Faulty Powertrain Control Module (PCM)

How to Fix the DTC P1477 Ford?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1477 Ford code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P1477 Ford code?

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Information for Specific Ford Models

P1477 1997 Ford F150 — Medium Cooling Fan Control Primary Circuit Failure
P1477 1998 Ford F150 — Medium Cooling Fan Control Primary Circuit Failure
P1477 1999 Ford F150 — Medium Cooling Fan Control Primary Circuit Failure
P1477 2000 Ford F150 — Medium Cooling Fan Control Primary Circuit Failure
P1477 2001 Ford F150 — Medium Cooling Fan Control Primary Circuit Failure
P1477 2002 Ford F150 — Medium Cooling Fan Control Primary Circuit Failure
P1477 2003 Ford F150 — Medium Cooling Fan Control Primary Circuit Failure
P1477 2006 Ford Fusion — Medium Cooling Fan Control Primary Circuit Failure
P1477 2007 Ford Fusion — Medium Cooling Fan Control Primary Circuit Failure
P1477 2008 Ford Fusion — Medium Cooling Fan Control Primary Circuit Failure
P1477 2009 Ford Fusion — Medium Cooling Fan Control Primary Circuit Failure
P1477 2010 Ford Fusion — Medium Cooling Fan Control Primary Circuit Failure
P1477 2011 Ford Fusion — Medium Cooling Fan Control Primary Circuit Failure
P1477 2012 Ford Fusion — Medium Cooling Fan Control Primary Circuit Failure

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.