Possible causes – Rear Air/Fuel Ratio Sensor Bank 1 Sensor 1 harness is open or shorted– Rear Air/Fuel Ratio Sensor Bank 1 Sensor 1 circuit poor electrical connection– Faulty Rear Air/Fuel Ratio Sensor Bank 1 Sensor 1 Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P2251 LEXUS OBD Code Description The rear…