Code result
P2249
O2 Sensor Reference Voltage Circuit Low
High severity
What it means
Bank 2 counterpart to P2245. The reference voltage on bank 2, sensor 1 is below the lower threshold — typically a short to ground or failed ECU output.
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
Reference line shorted to ground
highOne of the most commonly reported causes for this code — check this first.
ECU reference output failed
lowLess common, but worth ruling out after the more likely causes.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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