Code result
P0409
Exhaust Gas Recirculation Sensor \"B\" Circuit High
Moderate severity
What it means
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.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Sensor circuit shorted to supply
highOne of the most commonly reported causes for this code — check this first.
EGR position sensor B failed
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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