P2200
NOx Sensor Circuit Bank 1 Sensor 1
Auxiliary emissions control
Generic OBD-II
Medium
What it means
P2200 means the PCM has detected a fault in the bank 1, sensor 1 NOx (nitrogen-oxide) sensor circuit. This sensor measures NOx in the exhaust for emissions control and, on diesels, SCR/DEF dosing. The car usually still drives normally, but the fault will fail emissions and on many diesels can lead to a reduced-power derate if ignored.
Medium
Can I keep driving? Usually driveable, but it will fail emissions and, on many diesels, can trigger a reduced-power derate countdown, so don't leave it indefinitely.
Common symptoms
What you'll notice
- Check-engine light on
- Failed or incomplete emissions readiness
- On diesels: possible SCR/DEF warnings or a reduced-power (derate) countdown
- Often no noticeable change in how the engine drives
Common causes
Most likely first
- Faulty NOx sensor (bank 1, sensor 1)Likely
- Open or shorted NOx sensor wiring / harnessCommon
- Poor connector contact or corrosion at the sensor plugCommon
- Exhaust leak or contamination affecting the sensor readingLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check for related NOx codes (P2201-P2203).
- Inspect the NOx sensor connector and harness for damage, corrosion, and heat/chafe points.
- Check for exhaust leaks near the sensor that could skew its reading.
- Verify power and ground to the sensor module against spec.
- If the circuit checks out, replace the NOx sensor as specified (it is a combined sensor/module).
FAQ
Quick answers
Is it safe to drive with P2200?+
Mechanically it usually drives normally, but it will fail emissions and on many diesels can start a reduced-power derate countdown, so have it addressed.
Can I just clear P2200?+
It returns once the sensor runs again unless the wiring or the sensor itself is repaired.
Related codes
Often seen with P2200
Read & clear P2200 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