Code result
P2243
O2 Sensor Reference Voltage Circuit
High severity
What it means
The reference voltage line that powers the wide-band sensor cell on bank 1 sensor 1 is missing or out of tolerance. Without correct reference, the AFR calculation is invalid.
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 voltage line open
highOne of the most commonly reported causes for this code — check this first.
Wide-band sensor failed
mediumA plausible cause — test and verify before replacing parts.
Related help
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