2006 Mercury Mariner P2272 O2 Sensor Bank 1 Fault: Check Engine Light Still On After Replacement
I own a 2006 Mercury Mariner with a 3.0L engine. The check engine light has come on, and the diagnostic code displayed is P2272, which indicates a fault with the oxygen sensor in Bank 1. I have already replaced the oxygen sensor, but the check engine light remains on. Could there be another issue? Is it possible that the wrong sensor was installed or that additional diagnostics are needed?
Verify the exact trouble code — P2272 refers to Bank 1 Sensor 1, not Bank 2. Ensure you replaced the correct oxygen sensor. Double-check the OBD2 scan tool readings and confirm that the code is accurately reported before assuming a replacement issue.