P0409 - Exhaust Gas Recirculation Sensor B Circuit

The ECM detected a fault in the EGR sensor B circuit.

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Common Next Steps

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Related Inspection

Code Overview

The ECM detected a fault in the EGR sensor B circuit.

Common Causes

• Failed EGR sensor
• Damaged wiring or connector
• Control circuit issue

Diagnostic Steps

1. Inspect the EGR sensor connector and harness
2. Check command and feedback data if supported
3. Inspect the EGR valve and passages for buildup

Likely Repairs & Cost Guides

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Related OBD Codes

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Next Steps

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