P0134 – O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
- System
- Emissions
- Dashboard light
- Check engine light (MIL)
- Check-engine blink code
- —
- Applies to
- Generic OBD-II meaning. Not every code is used by this car.
- Description
- O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
- Detection / symptoms
- 1.Check engine light on
- Possible causes
- 1.Bad O2 (oxygen) sensor 2.Bad heater circuit in the O2 sensor 3.Wiring or connector to the sensor frayed / broken 4.Blown heater circuit fuse 5.Holes in the exhaust system 6.PCM failure
- What to check
- 1.Read the code and live data with an OBD-II scanner 2.Look for exhaust or vacuum leaks and check the wiring of the sensor or valve 3.Test the part before replacing it 4.Fix the cause, clear the code and test-drive
- Confidence
- medium (generic OBD-II definition, not checked against the factory manual for this car)
Generic OBD-II meaning (obd-codes.com), not checked against this car's factory manual. Clear the code and test-drive to confirm it returns. Search all fault codes · Common problems · Warning lights

