Code result
P225A
NOx Sensor Calibration Memory
High severity
What it means
The factory calibration memory of the NOx sensor on bank 1 sensor 1 cannot be read or contains a checksum error. Each NOx sensor ships with a unique calibration table programmed at the factory.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Sensor calibration memory corrupt
highOne of the most commonly reported causes for this code — check this first.
Module software outdated, reflash may resolve
lowLess common, but worth ruling out after the more likely causes.
Supply voltage outside specification
lowLess common, but worth ruling out after the more likely causes.
Related help
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