Code result
P2AC3
Intake Air O2 Sensor Reference Voltage Circuit/Open Bank 2
Moderate severity
What it means
The reference voltage supplied to the intake air oxygen sensor on bank 2 reports a circuit fault/open condition. Lambda measurement on the intake side is unreliable.
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
Open in reference voltage wire
highOne of the most commonly reported causes for this code — check this first.
Intake air O2 sensor failed
mediumA plausible cause — test and verify before replacing parts.
Pin pushed back out of connector body
lowLess common, but worth ruling out after the more likely causes.
Related help
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