Code result
P2A10
O2 Sensor Negative Voltage Bank 2 Sensor 2
Moderate severity
What it means
The ECM detects a negative voltage on the signal line of oxygen sensor 2 on bank 2. This is unusual for narrow-band sensors and often indicates a short to a negative reference, ground offset, or a wide-band sensor wired incorrectly.
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
Signal wire shorted to negative reference
highOne of the most commonly reported causes for this code — check this first.
Ground offset between sensor and ECM
mediumA plausible cause — test and verify before replacing parts.
Related help
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