Possible causes

– Faulty Heated Oxygen Sensor Bank 1 Sensor 2
– Heated Oxygen Sensor Bank 1 Sensor 2 harness is open or shorted
– Heated Oxygen Sensor Bank 1 Sensor 2 circuit poor electrical connection

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P0054 Information for specific makes

P0054 FORD
P0054 ISUZU
P0054 MAZDA
P0054 SUZUKI
P0054 BUICK
P0054 CADILLAC
P0054 CHEVROLET
P0054 GMC
P0054 PONTIAC
P0054 SATURN