My bmw 2007 328i only fcome on when i unplug it from the temperature sensor but

There are multiple possible causes as to why the fan may not turn on. First, does it turn on with the air conditioning system turned on? This can help give clues. This vehicle utilizes a digital motor electronics control module (DME) which has multiple inputs that control operation of the cooling fan based on information received regarding need. Fuse F69 protects the cooling fan circuit. But other components working in concert with each other will direct the need of the fan to turn on. Testing really needs to be performed by an experienced technician familiar with these BMW's using high end diagnostic equipment.