P0040 Code Definition
P0040 O2 Sensor Signals Swapped Bank 1 Sensor 1 / Bank 2 Sensor 1
What Does the Engine Code P0040 Mean?
Character "P" in the first position of Diagnostic Trouble Code (DTC) represents the powertrain system (engine and transmission), "0" in the second position means that this is a generic OBD-II (OBD2) DTC. "0" in the third character position in a DTC indicates that the fuel and air metering and auxiliary emission controls is experiencing a malfunction. The last two characters "40" is DTC number. OBD2 Diagnostic Trouble Code P0040 means that O2 Sensor Signals Swapped Bank 1 Sensor 1 / Bank 2 Sensor 1 has been detected.
Carly Universal Scanner
How Serious Is the Code P0040?
This issue is not critical yet. Make sure that it is current and fix it early before this leads to more severe issues.
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