P0409
Exhaust Gas Recirculation Sensor \"B\" Circuit High
Exhaust Gas Recirculation Sensor "B" Circuit High: the signal voltage is above the expected range. Without valid EGR feedback the ECU disables exhaust gas recirculation and may set further EGR codes.
Exhaust Gas Recirculation Sensor "B" Circuit High: the signal voltage is above the expected range. Without valid EGR feedback the ECU disables exhaust gas recirculation and may set further EGR codes.
Common causes
- high
Sensor circuit shorted to supply
One of the most commonly reported causes for this code — check this first.
Typical part cost: $70-440
- medium
EGR position sensor B failed
A plausible cause — test and verify before replacing parts.
Typical part cost: $70-440
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P0409 mean?
P0409 means "Exhaust Gas Recirculation Sensor \"B\" Circuit High". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P0409?
sensor circuit shorted to supply; egr position sensor b failed; connector pins corroded - high contact resistance — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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