OBD codes / P0140
P0140
ModerateO2 Sensor Circuit No Activity Detected (Bank 1, Sensor 2)
Get it looked at soon to avoid further wear.
Likely causes
- failing oxygen sensor
- exhaust leak near the sensor
- wiring or connector fault
Common fixes
- replace the bank 1 sensor 2 O2 sensor
- check for exhaust leaks and inspect wiring
Seeing P0140 on your car? Get a diagnosis specific to your exact year, make and model.
Diagnose P0140 for my vehicleGeneric OBD-II reference. Manufacturer-specific behavior varies — confirm with a scan tool and, for safety-related codes, a professional inspection.