OBD-II code · Powertrain (generic, extended)
P2223 NOx Sensor Heater Sense Circuit Low (Bank 2)
NOx Sensor Heater Sense Circuit Low (Bank 2): the signal voltage is below the expected range. The NOx sensor heater brings the sensor to operating temperature; a fault delays accurate NOx readings used for SCR control.
Is it safe to drive with P2223?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyShort to ground
- Less likelyConnector pins corroded - high contact resistance
- Less likelyHarness chafing through insulation
Symptoms
- Check engine light or NOx warning on
- AdBlue/DEF level or quality warning
- Possible no-start countdown after ignore period
- Failed emissions inspection (NOx)
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.5–3 h
- Emissions test
- Likely to fail
- Parts involved
- Nox Sensor
Related codes
- P2221NOx Sensor Heater Sense Circuit (Bank 2)
- P2220NOx Sensor Heater Control Circuit High (Bank 2)
- P2222NOx Sensor Heater Sense Circuit Range/Performance (Bank 2)
- P2224NOx Sensor Heater Sense Circuit High (Bank 2)
- P2225NOx Sensor Heater Sense Circuit Intermittent (Bank 2)
- P2226Barometric Pressure Circuit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.