Code result
P220B
NOx Sensor Supply Voltage Circuit
High severity
What it means
The supply voltage rail to the NOx sensor on bank 1 sensor 2 is faulty — typically a fuse, harness break, or short. NOx sensors need a clean stable supply for the heater and the wide-band measurement cell.
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
Supply rail fault
highOne of the most commonly reported causes for this code — check this first.
Related help
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