Code result
P2AC5
Intake Air O2 Sensor Reference Voltage Circuit Low Bank 2
Moderate severity
What it means
The reference voltage supplied to the intake air oxygen sensor on bank 2 reports a low 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
Reference wire shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Internal short in sensor reference
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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