OBD-II code · Powertrain (generic, extended)
P2204 NOx Sensor Circuit Intermittent (Bank 1)
The bank 1 NOx sensor signal drops out intermittently. Typical cause is a marginal connector, harness chafing near hot exhaust components, or thermal-cycling solder joints inside the smart sensor.
Is it safe to drive with P2204?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyConnector intermittent contact
- PossibleHarness chafed near exhaust
- Less likelyConnector with intermittent contact under vibration
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
- Often, with basic tools
- Typical labour
- 0.5–2.5 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Nox Sensor, Nox Sensor Wiring
Related codes
- P2200NOx Sensor Circuit (Bank 1)
- P2210NOx Sensor Circuit Intermittent (Bank 2)
- P2217NOx Sensor Circuit Intermittent (Bank 2)
- P2201NOx Sensor Range/Performance (Bank 1)
- P2202NOx Sensor Circuit Low (Bank 1)
- P2203NOx Sensor Circuit High (Bank 1)
- P2205NOx Sensor Heater Control Circuit (Bank 1)
- P2206NOx Sensor Circuit (Bank 2)
- P2207NOx Sensor Circuit Range/Performance (Bank 2)
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.