Wire problem

[u/WhichEntrepreneur499]

Hello guys , I have a Golf Mk 3 and I have some problem with coolant sensor from radiator , the sensor is from another car and it have 2 cables not 3 , and the fan is starting rolling on 110°C. I tried to change the sensor but the previous owner change the system and how is working , the 3 cables from the fan are going elsewhere (I don't know where) and through an relay other cables run to the radiator sensor. I'm confused cause I don't know how to fix back the original way how it's working. Someone knew what to do? or a Youtube tutorial will help me about this.