P2240 Citroen Oxygen (O2) Sensor Positive Current Control Circuit / Open (Bank 2 – Sensor 1)
– Air/Fuel Ratio Sensor Bank 2 circuit poor electrical connection
– Faulty Air/Fuel Ratio Sensor Bank 2
– Inappropriate fuel pressure
– Faulty fuel injectors
– Intake air leaks may be faulty
– Exhaust gas leaks
– High Fuel Consumption
– Excessive Smoke from Exhaust
The front air/fuel ratio (A/F) sensor (bank 2, sensor 1) is installed in the exhaust manifold and detects oxygen content in the exhaust gas. The front A/F sensor transmits output voltage to the powertrain control module (PCM). The PCM controls fuel injection duration by comparing the target air/fuel ratio with the front A/F sensor signal. The sensor includes the VS cell, the pump cell, the atmospheric reference cavity, the diffusion layer, and the heater, and it enables overall feedback control.