P2206
NOx Sensor Heater Control Circuit Low Bank 1 Sensor 1
Emissions / NOx sensor
Generic OBD-II
Low
What it means
P2206 means the control circuit for the bank 1, sensor 1 NOx sensor heater is reading low, usually from a short to ground, a bad connection, or a failed heater element. The NOx sensor needs its heater to reach operating temperature and monitor emissions, so it mostly affects the emissions system rather than daily driving — though some vehicles derate to protect it.
Low
Can I keep driving? Usually drivable — it's an emissions-sensor fault. Some vehicles limit power or DEF/SCR function to protect emissions, so don't leave it long.
Common symptoms
What you'll notice
- Check-engine light on
- Often no change in how the car drives
- Possible reduced power or emissions warning on diesels/SCR vehicles
- Fails an emissions/readiness test
Common causes
Most likely first
- Signal or heater wire shorted to ground (drives the control voltage low)Likely
- Faulty NOx sensor heater elementCommon
- Poor connection or corrosion at the NOx sensor connectorCommon
- Chafed or damaged sensor harnessLess often
- Rarely, a faulty ECM/sensor module driverLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and confirm it's the bank 1, sensor 1 NOx heater circuit.
- Inspect the NOx sensor connector and harness for a short to ground, corrosion, or chafing.
- Check the heater circuit resistance and confirm it gets power and a good ground.
- Because the sensor and its module are one assembly, a failed heater usually means sensor replacement.
- Clear the code and confirm the heater circuit stays in range after a drive cycle.
FAQ
Quick answers
Is it safe to drive with P2206?+
Generally yes, but on diesel/SCR vehicles the emissions system may derate or warn, so plan to fix it.
Can I just clear P2206?+
It returns until the heater circuit or NOx sensor is repaired.
Related codes
Often seen with P2206
Read & clear P2206 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