P06EA
NOx Sensor Processor Performance Bank 1 Sensor 1
An internal self-test in the control module reports a fault in its processing of the "NOx sensor processing, bank 1 sensor 1" value. The module computes and cross-checks this value redundantly inside its own processor; when the results disagree, the code sets. It points to a hardware or software fault inside the module itself, not to a defect of the external sensor. Causes are an internal processor or memory fault, corrupted control-module software, or low or disturbed module supply voltage.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: hard
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)
Common causes
Ordered by how often each turns out to be the cause.
- Internal software anomalyCommon
- Module software outdated, reflash may resolveLess likely
- Supply voltage outside specificationLess likely
Parts involved
- ECU Internal Processing
- NOX Sensor B1s1
P06EA is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.