Be careful about hot wiring something that blew a 30 amp fuse. If there is a hard short, you could do lot of damage toyour electrical system.

Since you ask about how to measure the current, I assume you don't own a clamp-on ammeter or a shunt resistor. A new 25 and 30 amp fuse makes for a crudely effective ammeter.

Like the older MBs with the resistors, the fan controller is located at the fan, above the passenger side floor board. Like the resistors, the integrated circuit fan controller reduces the voltage by turning it into heat. There could be some insulation or other material that has dropped down onto the controller, causing the burning smell. A loose connection at the fan or bad fan bearings could also increase the current, causing the wire insulation to burn. Does it smell like burning paper or burning rubber?

Either way, you need to remove the cover above the front passenger floor board to have a look.