O2 sensor on 2006 Dodge Sprinter 3500

Where is the 02 sensor located on a 3500 sprinter please

Asked by for the 2006 Dodge Sprinter 3500
02 sensor or the air sensor that fails? The Air sensor that failed on me 3 times is located about halfway down the radiator on the drivers side. The Air temp. sensor failure cuts your engine power about 35% and the engine light goes on. This is much more common than the 02 sensor failing.