NOx sensors
P2200–P2204, P229E and P229F: NOx sensor fault codes
P2200 to P2204 refer to bank 1, sensor 1; P229E and P229F refer to bank 1, sensor 2. The codes distinguish circuit, operating-range and signal conditions, not automatically their cause.
At a glance
What the codes tell you
- P2200
- NOx sensor—circuit (bank 1, sensor 1).
- P2201
- NOx sensor—range/performance (bank 1, sensor 1).
- P2202
- NOx sensor—signal low (bank 1, sensor 1).
- P2203
- NOx sensor—signal high (bank 1, sensor 1).
- P2204
- NOx sensor—intermittent/erratic signal (bank 1, sensor 1).
- P229E
- NOx sensor—circuit (bank 1, sensor 2).
- P229F
- NOx sensor—range/performance (bank 1, sensor 2).
How the entries differ
- For sensor 1, P2200 to P2204 distinguish circuit, operating range, low signal, high signal and an intermittently implausible signal.
- P229E and P229F concern sensor 2’s circuit and operating range respectively.
- Whether sensor 1 is before and sensor 2 after the SCR catalyst must be checked against the vehicle’s actual exhaust layout.
What is not yet established
- A NOx sensor code is not an automatic instruction to replace the sensor.
- Installation position, supply, heating, communication and operating conditions all form part of the assessment.
- The code describes the control unit’s assessment. It determines neither which component needs replacing nor the repair required.
- Manufacturer-specific descriptions, status, freeze-frame data and live readings can materially change the interpretation.
Diagnostic information that helps next
A reliable assessment does not consider the code in isolation. The following information turns a number into a fault condition that can be investigated:
- Full code, including bank, sensor and status
- Power supply, ground, heating and data communication
- Live NOx reading at a suitable exhaust temperature
- Related SCR, dosing and exhaust-leak findings
Frequently asked questions about P2200, P2201, P2202, P2203, P2204, P229E, P229F
What do fault codes P2200, P2201, P2202, P2203, P2204, P229E, P229F mean?
P2200: NOx sensor—circuit (bank 1, sensor 1). P2201: NOx sensor—range/performance (bank 1, sensor 1). P2202: NOx sensor—signal low (bank 1, sensor 1). P2203: NOx sensor—signal high (bank 1, sensor 1). P2204: NOx sensor—intermittent/erratic signal (bank 1, sensor 1). P229E: NOx sensor—circuit (bank 1, sensor 2). P229F: NOx sensor—range/performance (bank 1, sensor 2).
Which component needs replacing for P2200?
The code does not determine that. The full diagnostic description, fault status, freeze-frame data, live readings and vehicle-specific system checks determine the appropriate repair.
What information helps with diagnosis?
Useful information includes Full code, including bank, sensor and status, Power supply, ground, heating and data communication, Live NOx reading at a suitable exhaust temperature, Related SCR, dosing and exhaust-leak findings.
Traceable sources
Sources and scope
The descriptions are our own factual explanations of standardised generic OBD definitions. Manufacturer-specific P1xxx codes and differing manufacturer descriptions are not given blanket interpretations here.