Oxygen Sensor Circuit No Activity Detected (Bank 1 Sensor 2)
Oxygen sensor 2 on bank 1 isn't sending a signal.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The oxygen sensor after the catalytic converter is not sending any voltage signal back to the engine control module, indicating it's either broken or disconnected.
What the computer is actually seeing
The computer looks for a voltage signal from the bank 1 sensor 2 oxygen sensor. When it's not seen, it triggers this code. Expect a voltage between 0.1V and 0.9V under normal operating conditions.
What a healthy reading looks like
Oxygen sensors should output 0.1V (rich) to 0.9V (lean). If sensor is healthy, during operation it should oscillate between these values.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect the wiring and connector of the bank 1 sensor 2 O2 sensor for breaks, corrosion, or loose connections. If any issues found, repair and retest.
- 22. Use a multimeter to check for voltage at the oxygen sensor connector while the engine is running. Expected voltage should be between 0.1V and 0.9V.
- 3 a. If no voltage is present, check the upstream wiring and the engine control module (ECM).
- 43. If the sensor is receiving voltage but still not responding, replace the bank 1 sensor 2 O2 sensor and retest.
Common causes
- Faulty bank 1 sensor 2 oxygen sensor
- Wiring or connector issues in the O2 sensor circuit
- Blown fuse or issues in the ECM
- Exhaust leaks prior to the sensor that can affect readings
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but fuel economy may be affected and it could lead to further issues if ignored.
Will the code come back after clearing it?
It might if the underlying issue isn't fixed. If the sensor is faulty or there's a wiring issue, it will trigger again.
Why does this code pair with other oxygen sensor codes?
Multiple oxygen sensor codes can occur due to shared wiring or issues in the exhaust that affect multiple sensors.
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