P2200 — NOx Sensor Circuit (Bank 1 Sensor 1)
NOx sensor circuit fault (upstream / bank 1 sensor 1).
P2200 indicates an electrical or signal fault from the upstream NOx sensor — the one mounted before the SCR catalyst. The ECU relies on this signal to calculate dosing demand, so a faulty upstream sensor quickly triggers warning lights and the AdBlue countdown.
P2200 symptoms
- AdBlue / Check Engine warning
- AdBlue countdown initiated
- Sister code P2202 often appears in pair
- Limp mode under load
Common causes of P2200
Upstream NOx sensor element failure
Thermal cycling degrades the sensor element; common above 70k miles.
Wiring damage
Heat damage to the loom near the manifold.
Exhaust leak before sensor
Air ingress upstream skews the signal.
Soot contamination
Heavy soot from a stalled regen can poison the sensor.
Vehicles affected by P2200
- • Mercedes Sprinter, Vito, C-Class, E-Class
- • BMW X5, 5 Series, 3 Series, X3
- • Audi A6, Q5, Q7
- • VW Crafter, Touareg, Tiguan
- • Ford Transit, Ranger, Kuga
- • Land Rover Discovery, Range Rover
P2200 diagnostic process
- Live data: upstream NOx mV / ppm
- Heater circuit resistance test
- Loom and connector inspection
- Exhaust leak test upstream of sensor
Common P2200 repairs
- Replace upstream NOx sensor with OE-coded part
- Code new sensor to vehicle
- Repair wiring / connector damage
- Address upstream exhaust leak
- Reset adaptations and clear stored codes
Related services
Related coverage areas
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Google Reviews
5 / 5
Based on 293+ Google reviews for our sister business Fast Lane Performance — the same team behind Fastlane AdBlue Solutions.
Read all reviews on Google →P2200 FAQs
Yes — left unresolved, P2200 typically progresses from a dashboard warning to limp mode, then to the AdBlue 'no engine start in X miles' countdown. The ECU is designed to enforce emissions compliance, so it will not clear itself by driving. A specialist diagnosis is needed.