The Selective Catalytic Reduction (SCR) system injects Diesel Exhaust Fluid (DEF) into the exhaust, NOx trap, and Catalytic Converter (TWC). To do this, it uses the injection reduction valve.
Due to the injection of Diesel Combustion Gas Fluid, a higher temperature of the Diesel Particulate Filter (DPF) is obtained, thus having an optimal performance of itself. In addition, there is a reduction of exhaust to the atmosphere.
The storage of the P2055 OBDII diagnostic code is due to the Powertrain Control Module (PCM) detects an excess voltage in the control circuit of the bank 1 reducer injection valve and the Selective Catalytic Reduction (SRC) system number 2.