Pack of 3 AMI/Midi Fuse 175 Amp High Current Fuse Bolt-on, commonly Used in Cars, Trucks, Construction Vehicles, Agricultural Machinery, caravans, Passenger Cars, Electrocar Golf Cart(175 A)

There's a big fuse for the auxiliary battery on those that commonly blows, usually when someone goes to replace the auxiliary battery without disconnecting the main. It's in a box directly on top of the main battery, you can either replaced the whole assembly or the fuses individually, it should be a 175amp midi fuse such as these.