AutoCodes – Ford – P0231 2009 Ford Fusion

P0231 2009 Ford Fusion Code - Fuel Pump Secondary Circuit Low

Quick Answer

The Powertrain Control Module (PCM) monitors the Fuel Pump Monitor (FPM) circuit. Common causes include Blown Fuel Pump fuse, Open Fuel Pump Monitor Circuit, Faulty Fuel Pump Relay. 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: P0231 2009 Ford Fusion indicates Fuel Pump Secondary Circuit Low.
Common causes: Common causes include Blown Fuel Pump fuse, Open Fuel Pump Monitor Circuit, Faulty Fuel Pump Relay.
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 3,357

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 Apr 13, 2019

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0231 2009 Ford Fusion Description

The Powertrain Control Module (PCM) monitors the Fuel Pump Monitor (FPM) circuit. The test fails if the PCM commands the fuel pump ON and B+ voltage is not detected on the FPM circuit.

OBDII Code P0231 2009 Ford Fusion - Fuel Pump Secondary Circuit Low - AutoCodes.com — P0231 2009 Ford Fusion Code - Fuel Pump Secondary Circuit Low

What does this mean?

What are the Possible Causes of the DTC P0231 2009 Ford Fusion?

Blown Fuel Pump fuse
Open Fuel Pump Monitor Circuit
Faulty Fuel Pump Relay
Damaged Engine Control Module (ECM)

How to Fix the DTC P0231 2009 Ford Fusion?

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 does this mean?

Code Tech Notes

For some FORD models:
1. Disconnect the inertia switch harness connector
2. Turn key to ON position (Engine OFF)
3. Measure voltage of circuit between inertia switch harness connector and ground
4. If battery voltage is found, replaced Inertia Switch
5. Clear codes.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0231 2009 Ford Fusion 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 P0231 2009 Ford Fusion code?

Need more information on how to fix the P0231 2009 Ford Fusion code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0231 2009 Ford Fusion code diagnosed by a professional: Find a repair shop in your area

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.

Frequently Asked Questions about P0231 2009 Ford Fusion Code

1. What does the OBDII code P0231 mean on a 2009 Ford Fusion?

P0231 indicates a low voltage condition in the fuel pump secondary circuit, which may prevent proper fuel delivery to the engine.

2. What are the common symptoms of code P0231 in a 2009 Ford Fusion?

Symptoms may include difficulty starting, engine stalling, poor acceleration, or complete engine failure.

3. What causes the P0231 code to trigger in a 2009 Ford Fusion?

Common causes include a faulty fuel pump relay, damaged wiring or connectors in the fuel pump circuit, a failing fuel pump, or a bad powertrain control module (PCM).

4. Can I drive my 2009 Ford Fusion with a P0231 code?

Driving with this code is not recommended as it can lead to engine stalling or failure, potentially creating unsafe driving conditions.

5. How do I diagnose the P0231 code on my 2009 Ford Fusion?

Diagnosis involves checking the fuel pump relay, inspecting the wiring and connectors in the fuel pump circuit, and testing the fuel pump for proper operation.

6. How can I fix the P0231 code on my 2009 Ford Fusion?

Repairs may include replacing a faulty fuel pump relay, repairing damaged wiring, replacing the fuel pump, or reprogramming the PCM if necessary.

7. How much does it cost to fix the P0231 code on a 2009 Ford Fusion?

Repair costs can vary. Replacing a fuel pump relay may cost $50â€“$100, whereas replacing a fuel pump could cost $300â€“$800 depending on labor rates.

8. Can a weak battery cause a P0231 code on a 2009 Ford Fusion?

Yes, a weak or failing battery can result in low voltage in the fuel pump circuit and trigger the P0231 code.

9. What tools are needed to troubleshoot a P0231 code on a 2009 Ford Fusion?

Essential tools include a digital multimeter to test voltage, an OBDII scanner to confirm the code, and wiring diagrams for the fuel pump circuit.

10. Is the P0231 code common in Ford vehicles like the 2009 Fusion?

While not extremely common, issues with the fuel pump circuit can occur in Ford vehicles, especially as they age or if thereâ€™s electrical system wear.