Code result
U029E
Lost Communication With NOx Sensor B
High severity
What it means
The vehicle bus reports loss of communication with NOx sensor B (smart sensor with own ECU). The SCR catalyst control loop loses its actual NOx feedback and may switch to substitute values.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Bus wiring open or shorted
highOne of the most commonly reported causes for this code — check this first.
Module without power or ground
mediumA plausible cause — test and verify before replacing parts.
Module failed
mediumA plausible cause — test and verify before replacing parts.
Related help
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