Fan Relay Low Speed Circuit Malfunction (Ford)
What does P1475 mean?
The P1475 code means the vehicle's onboard diagnostic system has detected: Fan Relay Low Speed Circuit Malfunction (Ford). This is a moderate severity code.
Common Symptoms
- Cooling fan does not operate on low speed
- Check Engine Light illuminated
- Engine temperature runs higher than normal in traffic
- AC condenser cooling may be reduced
- Fan only operates at high speed
Probable Causes (Ranked by Likelihood)
- Failed low-speed fan relay Very High
- Corroded relay socket in the fuse box High
- Open wiring between PCM and low-speed relay Moderate
- Faulty PCM relay driver Low
- Short to ground in the relay control circuit Low
Step-by-Step Diagnostic Procedure
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Locate the low-speed fan relay in the under-hood fuse box and swap with a relay of the same type.
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Inspect the relay socket for corrosion, burnt terminals, or melted plastic.
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Measure the PCM control signal at the relay coil terminal when low-speed fan is commanded.
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Test the relay coil and contacts with a multimeter. Coil resistance is typically 60 to 100 ohms.
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Check for wiring damage between the fuse box and the PCM.
Frequently Asked Questions
How do I find the correct relay?
Check the fuse box cover diagram or your owner's manual. The low-speed fan relay is usually labeled and may have a part number printed on it. Use an identical relay for swapping during diagnosis.
Can a corroded relay socket cause intermittent fan issues?
Yes. Corrosion in the relay socket increases resistance, which can cause the relay to work sometimes and fail other times. Cleaning the socket with electrical contact cleaner or replacing the fuse box panel can fix this.
Is this the same relay as P1473?
P1473 focuses on the entire low-speed fan circuit while P1475 specifically targets the relay portion of that circuit. The relay is the most common failure point in the low-speed fan circuit.