NHTSA Complaint #11407424 — 2011 BMW X5

VEHICLE'S ENGINE, BEING A DIESEL, REQUIRES NOX TRAP SYSTEM AND SCR SYSTEMS IN ORDER TO REDUCE HARMFUL EMISSIONS PER EPA STANDARDS. IN ORDER FOR THE SCR SYSTEM TO WORK PROPERLY, THE ENGINE MUST INJECT DEF (DIESEL-EXHAUST FLUID) INTO THE SCR SYSTEM. IN THE BMW X5 35D, THE DEF SYSTEM IS COMPRISED OF TWO TANKS: THE ACTIVE TANK AND THE PASSIVE TANK. A COMMON PROBLEM WITH THIS SYSTEM IS THE PRIMARY SENSOR OF THE PASSIVE TANK FAILING. THE SENSOR ITSELF FAILS, BUT THE ENTIRE TANK HAS TO BE REPLACED AS A RESULT OF THE SENSOR'S ISSUES, RESULTING IN SEVERAL THOUSANDS OF DOLLARS BEING SPENT DUE TO THE SENSOR ITSELF NOT BEING ABLE TO BE REPLACED IN THE ORIGINAL TANK. RECALL IS RECOMMENDED FOR BMW TO REPLACE THESE SENSORS AS THE FAILURE OF THESE SENSORS RESULTS IN THE SCR CATALYST SYSTEM FAILING TO OPERATE, WHICH IN TURN SIGNIFICANTLY DECREASES ENGINE PERFORMANCE, INCREASES EXHAUST EMISSIONS, AND RESULTS IN THE ENGINE NOT KNOWING THE CAPACITY ON WHICH TO OPERATE. THIS CAN BE DANGEROUS.