Your Bmw X3 engine control system detects a problem, the computer stores the diagnostic trouble
code U3639 in its memory.
To figure out what is wrong with your vehicle you must first extract the U3639 DTC For Bmw X3.
Another consequence of U3639 Bmw X3 engine overheating may be a blown head gasket. Heat makes aluminum swell almost three times faster than cast iron. Thermal stress can distort the head and make it swell in areas that are hottest like those between exhaust valves in adjoining cylinders, and areas that have restricted coolant flow like the narrow area that separates the cylinders. The typical aluminum head swells most in the middle, which can crush the head gasket if the head gets too hot. This will usually cause the head gasket to leak compression between adjacent cylinders, or leak coolant into the cylinders.
U3639 Bmw X3 DTC Meaning
Network Code - Problem is climate control system, lighting, airbags, etc.
SAE - Generic
Vehicle Speed Control And Idle Control System
Low Coolant Circuit
A/C System High Pressure High Temperature
While fuel economy was increased, acceleration was seriously compromised, and the loss of engine vacuum led to a dangerous loss of braking assist when the U3639 Bmw X3 code system was in four-cylinder mode. In addition to these issues, while the company proposed a hydraulically controlled system that could be switched from within the car, the version they implemented had to be manually changed in the engine compartment using hand tools.