P0406 Ford Code - Exhaust Gas Recirculation Sensor 'A' Circuit High
Quick Answer
The P0406 diagnostic trouble code for Ford vehicles indicates an issue with the Exhaust Gas Recirculation (EGR) Sensor 'A' Circuit being too high. Common causes include Faulty EGR Sensor: A malfunctioning EGR sensor can send incorrect voltage readings to the ECM, triggering the P0406 code, Malfunctioning EGR Valve: If the EGR valve fails to open or close properly, it can lead to high voltage readings in the EGR circuit, Wiring or Connector Issues: Corrosion, damage, or loose connections in the wiring or connectors of the EGR circuit can cause voltage irregularities. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
- What it means
- P0406 Ford indicates Exhaust Gas Recirculation Sensor 'A' Circuit High.
- Common causes
- Common causes include Faulty EGR Sensor: A malfunctioning EGR sensor can send incorrect voltage readings to the ECM, triggering the P0406 code, Malfunctioning EGR Valve: If the EGR valve fails to open or close properly, it can lead to high voltage readings in the EGR circuit, Wiring or Connector Issues: Corrosion, damage, or loose connections in the wiring or connectors of the EGR circuit can cause voltage irregularities.
- Severity
- Moderate - service should be scheduled soon.
- Can I drive?
- The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
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Code P0406 Ford Description
The P0406 diagnostic trouble code for Ford vehicles indicates an issue with the Exhaust Gas Recirculation (EGR) Sensor 'A' Circuit being too high. The EGR system is crucial in reducing harmful emissions by recirculating a portion of the exhaust gas back into the intake system to be re-burned. The EGR sensor monitors the EGR system's functionality and reports back to the engine control module (ECM). When the sensor detects that the EGR circuit voltage is higher than the specified range, it triggers the P0406 code.
Common Causes of P0406 Ford
- Faulty EGR Sensor: A malfunctioning EGR sensor can send incorrect voltage readings to the ECM, triggering the P0406 code.
- Malfunctioning EGR Valve: If the EGR valve fails to open or close properly, it can lead to high voltage readings in the EGR circuit.
- Wiring or Connector Issues: Corrosion, damage, or loose connections in the wiring or connectors of the EGR circuit can cause voltage irregularities.
- ECM Malfunction: A problem with the engine control module (ECM) can also be a potential cause of the P0406 code.
Symptoms of P0406 Ford
- Check Engine Light: The most common symptom associated with the P0406 code is the illumination of the Check Engine Light on the vehicle's dashboard.
- Reduced Fuel Efficiency: A malfunctioning EGR system can lead to decreased fuel efficiency and increased fuel consumption.
- Rough Idling: The engine may experience rough idling or even stalling due to improper EGR system operation.
- Hesitation or Misfiring: The vehicle may exhibit hesitation or misfiring during acceleration, especially at low speeds.
- Increased Emissions: Higher emissions levels may be detected during emissions testing due to the malfunctioning EGR system.
How to Fix P0406 Ford
- Diagnose the Issue: Use a diagnostic scanner to confirm the presence of the P0406 code and perform a thorough inspection of the EGR system components.
- Replace EGR Sensor: If the EGR sensor is faulty, replace it with a new sensor and ensure proper connection to the EGR circuit.
- Check EGR Valve: Inspect the EGR valve for proper operation and replace it if necessary.
- Repair Wiring/Connectors: Repair any damaged wiring or connectors in the EGR circuit to ensure proper voltage readings.
- Clear Codes and Test Drive: Clear the diagnostic trouble codes from the ECM, and test drive the vehicle to ensure that the issue has been resolved.
Cost to Fix P0406 Ford
The typical repair costs for addressing the P0406 code can vary depending on the specific cause of the issue and the labor rates in your area. On average, the cost of replacing an EGR sensor can range from $150 to $300, while replacing an EGR valve can cost between $200 and $400. Repairing wiring or connectors may add additional labor costs, bringing the total repair estimate to between $300 and $600. It's important to note that the actual cost can vary based on the vehicle make and model, as well as the location and specific diagnosis time at the auto repair shop. It's recommended to consult with a professional mechanic for an accurate cost estimate for your specific situation.
When is the Code Detected?
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Information for Specific Ford Models
- P0406 1997 Ford F150 — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 1998 Ford F150 — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 1999 Ford F150 — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2000 Ford F150 — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2001 Ford F150 — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2002 Ford F150 — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2003 Ford F150 — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2006 Ford Fusion — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2007 Ford Fusion — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2008 Ford Fusion — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2009 Ford Fusion — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2010 Ford Fusion — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2011 Ford Fusion — Exhaust Gas Recirculation Sensor 'A' Circuit High
- P0406 2012 Ford Fusion — Exhaust Gas Recirculation Sensor 'A' Circuit High
Frequently Asked Questions about P0406 Ford Code
No Frequently Asked Questions about P0406 Ford Code found.
Discuss the causes and fixes for P0406 Ford OBDII Code
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Have a P0108 and P0406 codes for a 2006 Ford Explorer. It is running a little rough so maybe P0406 is related to the ERG. What's my best approach to get these fixed?
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Actually both codes could cause the engine to run rough. You should start visual inspect both components (MAP Sensor and EGR Solenoid Valve) and if everything check OK, then clear the codes and check what codes comes back first.
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2004 Ford expedition 4.6 has a p0406 code installed new dpfe sensor egr solenoid and egr valve what could cause this code?
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Wow. Unfortunately I have nothing. I also checked a national database of repairs for your model year and the EGR valve is by far the most common problem. Here is the entire list
- Exhaust Gas Recirculation Valve
- Exhaust Gas Recirculation Pressure Sensor Hose
- Exhaust Gas Recirculation Pressure Sensor
- Exhaust Gas Recirculation Valve Gasket
- Vacuum Hose -
2011 ford ranger 4.0 v6 getting code 406, engine is running fine, have replaced egr valve and sensor, still get code when starting after clearing code it runs fine, when turn off engine and restart code reappears
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Unfortunately, other than the EGR Valve and Sensor I have not seen any other component setting the P0406 code. You could either double check the installation, make sure the connector is firmly connected, or check the wire from the EGR Valve to the Powertrain Control Module (PCM). The Grey wire should have battery voltage, and with the valve connected you should have around 5 Volts at the Violet/White wire.
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