P2219
NOx Sensor Heater Control Circuit Low Bank 2
Emissions / NOx sensor
Generic OBD-II
Medium
What it means
P2219 means the ECM has detected a low voltage in the heater control circuit of the bank 2 NOx sensor — typically a short to ground or high resistance in the wiring. The heater brings the NOx sensor up to operating temperature so it can measure exhaust nitrogen oxides. The engine drives normally, but the emissions and SCR system relies on this sensor, so the fault should be repaired.
Medium
Can I keep driving? Drivable — the engine runs normally, but the emissions/SCR system is affected, and some diesels may eventually limit power if emissions faults are ignored.
Common symptoms
What you'll notice
- Check-engine light on
- Often no change in how the engine drives
- Possible emissions-system or DEF/SCR warning on diesels
- Failed emissions test and higher NOx output
Common causes
Most likely first
- Short to ground or excessive resistance in the bank 2 NOx sensor heater control circuitLikely
- Open or shorted NOx sensor wiring harnessCommon
- Poor electrical connection or corrosion at the sensor connectorCommon
- Faulty NOx sensor heater elementLess often
How to diagnose & fix
Work through it in order
- Inspect the bank 2 NOx sensor connector and wiring for corrosion, chafing, or loose pins.
- Check the heater control circuit for a short to ground or high resistance.
- Confirm the sensor is getting its supply voltage and a clean ground.
- Review NOx sensor live data, then replace the NOx sensor if the circuit is good but the heater still reads low, and clear and re-test.
FAQ
Quick answers
Is it safe to drive with P2219?+
Yes short-term — the engine drives normally. But it affects emissions and the SCR system, and some diesels can move toward reduced power if emissions faults are ignored, so repair it before long.
Can I just clear P2219?+
It clears, but the low heater-control reading returns once the circuit is monitored again. Fix the wiring or replace the NOx sensor first.
Related codes
Often seen with P2219
Read & clear P2219 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