Cause
Faulty NOx sensor
The sensor measuring oxides of nitrogen across the after-treatment system on a diesel. Expensive, a genuine consumable, and its failure starts an emissions countdown rather than a driveability complaint — the vehicle drives normally while a speed restriction or a no-restart condition approaches.
Typically a moderate job.
Some of these codes mean you should stop driving
1 of the 44 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (44)
Codes where this is a likely explanation first, rather than merely a possible one.
- P2000 NOx Adsorber Efficiency Below Threshold — Bank 1 Likely for this code High
- P2001 NOx Adsorber Efficiency Below Threshold — Bank 2 Likely for this code High
- P20EE SCR NOx Catalyst Efficiency Below Threshold Bank 1 Catalyst 1 Likely for this code High
- P2200 NOx Sensor Circuit Bank 1 Sensor 1 Likely for this code High
- P2201 NOx Sensor Circuit Range/Performance Bank 1 Sensor 1 Likely for this code High
- P2202 NOx Sensor Circuit Low Bank 1 Sensor 1 Likely for this code High
- P2203 NOx Sensor Circuit High Bank 1 Sensor 1 Likely for this code High
- P2205 NOx Sensor Heater Control Circuit/Open Bank 1 Sensor 1 Likely for this code High
- P2206 NOx Sensor Heater Control Circuit Low Bank 1 Sensor 1 Likely for this code High
- P2207 NOx Sensor Heater Control Circuit High Bank 1 Sensor 1 Likely for this code High
- P2209 NOx Sensor Heater Sense Circuit Range/Performance Bank 1 Sensor 1 Likely for this code Moderate
- P2211 NOx Sensor Heater Sense Circuit High Bank 1 Sensor 1 Likely for this code Moderate
- P2213 NOx Sensor Circuit Bank 2 Likely for this code High
- P2214 NOx Sensor Circuit Range/Performance Bank 2 Likely for this code High
- P2215 NOx Sensor Circuit Low Input Bank 2 Likely for this code High
- P2216 NOx Sensor Circuit High Input Bank 2 Likely for this code High
- P2218 NOx Sensor Heater Control Circuit/Open Bank 2 Likely for this code High
- P2219 NOx Sensor Heater Control Circuit Low Bank 2 Likely for this code High
- P2220 NOx Sensor Heater Control Circuit High Bank 2 Likely for this code High
- P2222 NOx Sensor Heater Sense Circuit Range/Performance Bank 2 Likely for this code Moderate
- P2224 NOx Sensor Heater Sense Circuit High Bank 2 Likely for this code Moderate
- P225C NOx Sensor Performance - Signal Biased/Stuck High Bank 1 Sensor 1 Likely for this code Moderate
- P225D NOx Sensor Performance - Signal Biased/Stuck Low Bank 1 Sensor 1 Likely for this code High
- P229E NOx Sensor Circuit Bank 1 Sensor 2 Likely for this code Moderate
- P229F NOx Sensor Circuit Range/Performance Bank 1 Sensor 2 Likely for this code Moderate
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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