DTC P2096: General Description
The powertrain control module (PCM) detects oxygen content in the exhaust gas by the rear air/fuel ratio (A/F) sensor (bank 1, sensor 1), and it uses feedback control before the rear warm up three way catalytic converter (WU-TWC) (bank 1) to bring the air/fuel ratio close to the target air/fuel ratio. The target air/fuel ratio is adjusted by the rear secondary heated oxygen sensor (secondary HO2S (bank 1, sensor 2)) output so that the air/fuel ratio in the rear WU-TWC (bank 1) is optimized. When the rear A/F sensor (bank 1, sensor 1) cannot measure air/fuel ratio in the exhaust gas normally, a gap occurs to the actual air/fuel ratio. As a result, the gap causes a deviation in target air/fuel ratio control (after rear WU-TWC (bank 1)) which is determined by the rear secondary HO2S (bank 1, sensor 2). If the deviation exceeds a limit, the PCM detects a malfunction and stores a DTC.