P2220
NOx Sensor Heater Control Circuit High Bank 2
Auxiliary emissions control
Generic OBD-II
Medium
What it means
P2220 means the PCM detects a high-voltage (short-to-voltage or open) fault in the heater control circuit of the bank 2 NOx sensor. The heater brings the sensor to operating temperature so it can measure exhaust NOx; with the control circuit out of range the sensor can't do its emissions job. It usually traces to wiring or a failed NOx sensor.
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 2) with an internal heater faultLikely
- Short to voltage or open in the NOx heater control wiringCommon
- Poor connector contact or corrosion at the sensor plugCommon
- Bad ground causing the heater control circuit to read highLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check for related NOx heater codes (P2218, P2219, P2221).
- Inspect the bank 2 NOx sensor connector and heater wiring for damage, corrosion, and chafing.
- Check the heater control circuit for a short-to-voltage or open, and verify the ground against spec.
- Clear the code and monitor whether the heater control reading returns to range.
- If the circuit is good, replace the NOx sensor as specified (sensor and heater are one assembly).
FAQ
Quick answers
Is it safe to drive with P2220?+
It usually drives normally, but the sensor can't reach operating temperature, so it will fail emissions and on many diesels may start a derate countdown. Have it addressed.
Can I just clear P2220?+
It returns once the heater circuit runs again unless the high/short fault or the sensor is repaired.
Related codes
Often seen with P2220
Read & clear P2220 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