What does code P0166 mean?
No activity detected from oxygen sensor B2S3; the signal remains completely flat
OBD-II Code
P0166 — Oxygen Sensor Circuit No Activity Detected Bank 2 Sensor 3
No activity detected from oxygen sensor B2S3; the signal remains completely flat
Common symptoms
- Mixture not adjusted
- slight increase in fuel consumption
Possible causes
- Failed sensor
- cut wiring
- open circuit
Initial recommendation
Check harness continuity, inspect connector and replace oxygen sensor.
Safety notice
This information is for guidance only and does not replace a physical vehicle inspection or diagnosis by a qualified mechanic. If the vehicle has severe power loss, smoke, a fuel odor, overheating, brake or steering problems, or any unsafe behavior, avoid driving it and seek professional inspection.
Analyze this code with MecaOBD
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