Code result
P2A02
O2 Sensor Circuit Range/Performance Bank 1 Sensor 3
Moderate severity
What it means
The optional third oxygen sensor on bank 1 (typically downstream of a second catalyst) returns implausible values during long-term monitoring.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Sensor aging
highOne of the most commonly reported causes for this code — check this first.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Sensor mounting loose - signal damping
lowLess common, but worth ruling out after the more likely causes.
Related help
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