Code result
P2251
O2 Sensor Negative Current Control Circuit
High severity
What it means
The negative current control line (Vs−) of the wide-band lambda sensor on bank 1 sensor 1 is open or out of range. Used as the virtual ground reference for the Nernst 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
Vs− line open
highOne of the most commonly reported causes for this code — check this first.
Wide-band sensor failed
mediumA plausible cause — test and verify before replacing parts.
Related help
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