Code result
P2278
O2 Sensor Signals Swapped Bank 1 Sensor 3 / Bank 2 Sensor 3
High severity
What it means
The PCM detects that the O2 sensor signals from bank 1 sensor 3 and bank 2 sensor 3 are swapped — typically a wiring crossover after sensor replacement.
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
Wiring crossover after sensor replacement
highOne of the most commonly reported causes for this code — check this first.
Related help
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