my defrozer dont work

Do you mean the heater blower motor has failed or the blower works but you cannot direct air to the floor/windscreen/center vents? The heater blower is protected by a 7.5 Amp fuse that supplies power to the blower motor controller. The blower motor and heater relay is protected by a 60 Amp main fuse but that main fuse supplies power to many other circuits you would see many other circuits down if that fuse was blown. If heater relay is operating correctly the blue/yellow wire at the blower motor should have power.