Problem code P2270 OBDII refers to the Catalytic Converter (TWC) Oxygen (O2) Sensor. This is the number 2 sensor in bank 1. Its function is to control the efficiency of the TWC.
The Catalytic Converter aims to reduce exhaust emissions. If the PCM (Powertrain Control Module) detects that the O2 Sensor signal is stuck, this code is set. The stuck or blocked signal produced by the Oxygen Sensor indicates that the amount of air in the exhaust is excessive.