If you own a Ford Fusion, chances are you’ve encountered the “Power Steering Assist Fault” error. This warning can be alarming, especially if you experience sudden loss of steering assist, making the vehicle harder to maneuver. But don’t panic—this guide covers why it happens, what it means, and how you can fix it, whether you’re a DIY enthusiast or planning to visit a professional.
What Is the Power Steering Assist Fault?
In modern cars like the Ford Fusion, power steering is controlled by an Electric Power-Assisted Steering (EPAS) system, replacing the older hydraulic systems. When functioning properly, it makes steering smooth and effortless. The Power Steering Assist Fault warning signals a failure in this system, which may result in loss of power assistance.
Without this assistance, steering becomes much heavier, especially at low speeds, which can compromise safety.
Common Causes of Power Steering Assist Fault in Ford Fusion
Several factors can trigger this fault warning:
✅ Low or Contaminated Power Steering Fluid (for older hydraulic models, though Fusion mainly uses EPAS)
✅ Faulty Electric Power Steering (EPS) Motor
✅ Bad Torque Sensor or Steering Angle Sensor
✅ Blown Fuse or Faulty Relay in EPS Circuit
✅ Software Issues in the Power Steering Module
✅ Wiring Harness Problems or Loose Connections
✅ Battery or Alternator Issues – Low voltage can trigger EPS errors
✅ Control Module Malfunctions – Internal faults or corrupted software
How to Fix Power Steering Assist Fault in Ford Fusion
Let’s break down the step-by-step solutions, from basic checks to advanced repairs.
🔧 Step 1: Check for Trouble Codes (DTCs)
The first step is to scan your vehicle’s computer with an OBD-II scanner. Look for codes related to the steering system (C1xxx series) or power steering module.
- Common Codes:
- C102D: Steering Motor Fault
- U3000: Control Module Fault
- C1B00: Steering Angle Sensor Issue
🔎 Action:
- Plug the scanner into the OBD-II port (under the dashboard).
- Read the stored codes.
- Note any “Pending” or “Stored” codes.
This will point you to the root cause, whether it’s electrical, mechanical, or software-related.
🔧 Step 2: Check Battery Voltage and Alternator
Low system voltage can disable EPS functions.
🔎 Action:
- Measure battery voltage with a multimeter. It should be 12.6V (engine off) and 13.7–14.7V (engine running).
- If the battery is weak or the alternator isn’t charging, replace or repair as needed.
🔧 Step 3: Inspect Fuses and Relays
A blown fuse or faulty relay can cut off power to the EPS.
🔎 Action:
- Locate the power steering fuse in the fuse box (engine bay or interior). Refer to the owner’s manual for exact location.
- Check for any blown fuses or burnt relays. Replace as necessary.
🔧 Step 4: Inspect Wiring Harness and Connections
Over time, vibration and moisture can damage wiring to the EPS motor or control module.
🔎 Action:
- Inspect wiring to the EPS motor, torque sensor, and steering angle sensor.
- Look for frayed wires, corrosion, or loose connectors.
- Repair or replace damaged wiring.
🔧 Step 5: Perform a Steering Angle Calibration
If the steering angle sensor (SAS) loses calibration, it can cause assist faults.
🔎 Action:
- Use a professional-grade scan tool to reset and calibrate the SAS.
- Follow on-screen prompts or refer to a Ford service manual.
🔧 Step 6: Update or Reflash the EPS Module Software
Sometimes, software glitches in the Power Steering Control Module (PSCM) trigger assist faults.
🔎 Action:
- Visit a Ford dealership or trusted mechanic with access to the Ford Integrated Diagnostic System (IDS).
- Request a PSCM software update or reflash.
- In some cases, this resolves intermittent errors.
🔧 Step 7: Replace the Electric Power Steering Rack or Motor
If diagnostics reveal a faulty EPS motor or steering rack, replacement may be necessary.
🔎 Action:
- Replacement requires removing the steering rack assembly.
- This is a labor-intensive job best suited for professionals unless you have advanced skills.
💡 Tip: New or remanufactured EPS racks can cost between $800–$1500 plus labor.
Preventive Tips for Avoiding Future EPS Faults
✅ Maintain battery health – Regularly check voltage and charging system.
✅ Avoid deep water driving – Water intrusion can corrode wiring and modules.
✅ Drive carefully on rough roads – Reduces vibrations that damage EPS components.
✅ Service as recommended – Follow Ford’s maintenance schedule.
✅ Respond to warning lights promptly – Early diagnosis prevents bigger repairs.
When to See a Professional
While some fixes are DIY-friendly, others (like module reprogramming or rack replacement) require specialized tools and expertise. Seek professional help if:
🚩 The fault warning won’t clear after basic checks.
🚩 You notice strange noises, grinding, or stiff steering.
🚩 There’s visible damage to wiring or EPS components.
🚩 The EPS system needs a software update or replacement.
Cost to Fix Power Steering Assist Fault in Ford Fusion
| Repair Option | Estimated Cost (USD) |
|---|---|
| Battery or Alternator Replacement | $100–$400 |
| Fuse/Relay Replacement | $10–$50 |
| Wiring Harness Repair | $150–$400 |
| Steering Angle Calibration | $50–$150 |
| EPS Module Software Update | $100–$250 |
| EPS Rack/Motor Replacement | $800–$2000 |
💡 Note: DIY repairs can save money, but improper fixes can worsen the problem.
Conclusion
The Power Steering Assist Fault in your Ford Fusion may seem daunting, but armed with the right knowledge, you can identify and resolve the issue effectively. Whether it’s a simple battery check, a wiring fix, or a more complex EPS module update, each step brings you closer to restoring smooth steering.
Don’t ignore the warning light—act early to ensure your safety and extend your vehicle’s life.
Frequently Asked Questions (FAQs)
❓ How do I reset the Power Steering Assist Fault on a Ford Fusion?
A simple battery disconnect (negative terminal) for 15 minutes may reset the system. However, if the root issue isn’t fixed, the warning will return.
❓ Can I drive with a Power Steering Assist Fault?
It’s possible but not recommended. Steering will be much harder, especially at low speeds, increasing accident risk.
❓ Does a Ford Fusion use hydraulic or electric power steering?
Ford Fusion models from 2010 onward use Electric Power-Assisted Steering (EPAS).
❓ How much does it cost to fix the EPS system in a Ford Fusion?
Depending on the cause, repair costs range from $50 to over $2000.
❓ Is EPS failure a common problem in Ford Fusions?
It’s a known issue, particularly in older models or vehicles with high mileage, but not inevitable with proper care.