Code result
P22B0
O2 Sensor Reference Voltage Circuit Low
High severity
What it means
O2 reference voltage on bank 1 sensor 2 below lower plausibility — short to ground. A drifted or sluggish lambda sensor lets the mixture run lean or rich without correction — fuel economy and emissions suffer immediately.
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
Short to ground
highOne of the most commonly reported causes for this code — check this first.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Harness chafing through insulation
lowLess common, but worth ruling out after the more likely causes.
Related help
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