DTC code
P0407
EGR Sensor B Circuit Low
Technical guide
reference — not individually verifiedSymptoms
- Check engine light on
- Pinging or knocking under load
- Power loss and hesitation
- Possible rough idle
- Failed emissions inspection (NOx)
Probable causes
- high: EGR sensor B internally faulty
- medium: Signal wire shorted to ground
- low: Connector corroded
Diagnostic steps
Check the components involved: egr position sensor, egr pressure sensor, sensor wiring. Verify wiring and connectors before replacing any part. Job difficulty: medium (workshop equipment required). Typical European range — 120-500 EUR, 0.5-2 h. Reference values only.
Cross-checked technical synthesis (QA). It does not replace the manufacturer's procedure.
AI here is a librarian: this page shows only what mechanics confirmed, or says “unknown”. It never suggests a diagnosis — MECCANIC interprets the code, never your car.
0 confirmed cases on P0407
Nothing confirmed yet for this code. No guess is offered on purpose.
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