Was it parked for a while before this happened? Have you seen any rodent activity? If the fuse is popping soon as you are plugging it in then you possibly have a short to ground on the load side between the junction block and the amp or in the amp itself. If you have a voltmeter, switch it to continuity and test the load side of the fuse slot to ground (body of the car) after unplugging the amp. The amp is in the cargo area (see image below) pull the plugs off that to remove ground. If you have continuity after unplugging the amp you have a short somewhere in the line. Use the diagrams below to follow the line and look for pinched wires or damage. You could also go through and unplug some of the wire-to-wire connectors and test again to narrow down which section has the short. I would check the sections under the doorsills first. If there was no continuity in the line after unplugging the amp then the problem is in the amp itself.
The red dots mark the power line and associated connectors.
The red dots mark the power line and associated connectors.


