P0163
O2 Sensor Circuit Low Voltage Bank 2 Sensor 3
Oxygen sensor / fuel metering
Generic OBD-II
Medium
What it means
P0163 means the bank 2, sensor 3 oxygen sensor — a downstream sensor after the catalytic converter — is reading an abnormally low voltage, indicating a lean signal or a short to ground. This sensor mainly monitors converter efficiency, so the fault affects emissions monitoring more than how the car drives.
Medium
Can I keep driving? Yes — this downstream sensor code doesn't affect drivability; fix it to pass emissions and keep converter monitoring working.
Common symptoms
What you'll notice
- Check-engine light on
- Usually no noticeable change in driving
- Possible slight drop in fuel economy
- May fail an emissions test
Common causes
Most likely first
- Signal wire shorted to ground, or an open in the circuitLikely
- Aged or contaminated bank 2, sensor 3 oxygen sensorCommon
- Exhaust leak near the sensor drawing in outside air (lean signal)Common
- Corroded or loose connector at the sensorLess often
- Rarely, an ECM faultLess often
How to diagnose & fix
Work through it in order
- Read live data to confirm the sensor voltage is stuck low.
- Inspect the sensor wiring for a short to ground or an open.
- Check for exhaust leaks ahead of the sensor.
- Replace the bank 2, sensor 3 oxygen sensor if the wiring is good.
- Clear the code and re-run the readiness monitor.
FAQ
Quick answers
Is it safe to drive with P0163?+
Yes. It's an emissions-monitoring code with no real drivability impact. Fix it for emissions testing and proper converter monitoring.
Can I just clear P0163?+
Clearing it is temporary; if the sensor or its wiring is faulty the code returns once the monitor runs.
Related codes
Often seen with P0163
Read & clear P0163 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX