P0403: Exhaust Gas Recirculation Circuit Malfunction
Can you still drive? Yes, short-term driving is acceptable. The engine may ping under load, which can cause damage over time if ignored.
What Does P0403 Mean?
Code P0403 indicates an electrical malfunction in the EGR (Exhaust Gas Recirculation) valve control circuit. The ECM has detected a problem with the wiring, connector, or electronic EGR valve itself. This prevents the ECM from properly controlling the amount of exhaust gas recirculated into the intake.
Need to read your codes?
An OBD-II scanner lets you read and clear diagnostic trouble codes from your vehicle's computer. Most scanners work with any car made after 1996.
Browse OBD-II Scanners on AmazonCommon Causes
- Faulty EGR valve solenoid
- Damaged wiring or corroded connector to EGR valve
- Short circuit in EGR control circuit
- Failed EGR valve actuator motor
- ECM driver circuit fault
Symptoms
- Check engine light on
- Rough idle
- Engine pinging or knocking
- Failed emissions test
- Reduced fuel efficiency
Diagnostic Steps
- 1Read freeze frame data to identify conditions during fault
- 2Inspect EGR valve connector and wiring for damage or corrosion
- 3Measure EGR solenoid resistance with a multimeter
- 4Check for voltage at the EGR valve connector with key on
- 5Command the EGR valve open and closed using a scan tool and verify operation
- 6Test ECM output to EGR valve circuit
Recommended Parts & Tools
electrical connector cleaner
Estimated Repair Cost
| Type | Estimated Cost |
|---|---|
| Total Repair Cost Range | $100 - $450 |
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Chat with AI About P0403Commonly Affected Vehicles
Related Recalls
5 Active Recalls — 2026 Ford Explorer
The following NHTSA safety recalls have been issued for this vehicle. Contact your dealer to check if your vehicle is affected.
VISIBILITY:WINDSHIELD
Ford Motor Company (Ford) is recalling certain 2025-2026 Lincoln Corsair, Lincoln Aviator, and Explorer vehicles. The windshield glass may have visible air bubbles, which can obscure the driver's visibility. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 205, "Glazing Materials."
Remedy: Dealers will inspect and replace the windshield as necessary, free of charge. Owner notification letters were mailed November 6, 2025. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 25C60. Vehicle Identification Numbers (VINs) involved in this recall become searchable on NHTSA.gov beginning October 27, 2025.
ENGINE
Ford Motor Company (Ford) is recalling certain 2026 Explorer, Mustang, Lincoln Corsair, and 2025 Maverick vehicles. The cylinder head may have been improperly manufactured, which can cause the ball plugs to fail, resulting in an oil leak.
Remedy: Dealers will replace the cylinder head assembly, free of charge. All affected vehicles are still within dealership inventory and therefore no owner notification letters will be mailed. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 25SD3. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on November 24, 2025.
TRAILER HITCHES
Ford Motor Company (Ford) is recalling certain 2024-2026 Explorer and 2024-2026 Lincoln Aviator vehicles. The trailer hitch assembly bolts may be loose.
Remedy: Dealers will inspect and tighten the trailer hitch bolts, or replace them as necessary, free of charge. Owner notification letters were mailed October 29, 2025. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 25SA3. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on October 15, 2025.
VISIBILITY:WINDSHIELD
Ford Motor Company (Ford) is recalling certain 2026 Explorer vehicles. During manufacturing, the windshield may not have been properly bonded to the vehicle, allowing it to detach in a crash. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 212, "Windshield Mounting."
Remedy: Dealers will remove and replace the windshield, free charge. Owner notification letters were mailed January 30, 2026. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 26C02. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on January 22, 2026.
EXTERIOR LIGHTING:HEADLIGHTS
Ford Motor Company (Ford) is recalling certain 2025-2026 Explorer vehicles. The Dynamic Bending Light (DBL) system software may cause the passenger-side headlight to turn in the wrong direction when driving through curves in the road. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, " Lamps, Reflective Devices, and Associated Equipment."
Remedy: The headlight control module software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. Owner notification letters are expected to be mailed March 23, 2026. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 26C12. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on March 5, 2026.
Data provided by the National Highway Traffic Safety Administration (NHTSA).
Frequently Asked Questions
Is P0403 the same as P0401?
No. P0401 means insufficient EGR flow, while P0403 indicates an electrical problem in the EGR circuit. P0401 is a flow issue, and P0403 is a wiring or component electrical failure.
Will P0403 cause my car to fail emissions?
Yes. Any illuminated check engine light will automatically fail an emissions test in most states, and EGR system faults directly affect emissions output.
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