Ignition issues?

Tonight I was backing down the ramp I was able to trim the motor down then when I went to start it I heard a click then nothing. The 30amp fuse right off the battery was blown. Replaced the fuse and still had nothing. Was not able to trim the motor. I know the battery is good because livewell pump comes directly off the battery and that turned right on. I had it out last weekend with zero problems. I'm thinking ignition issues kill switch/ignition switch but I really don't know.

 

I've doubled checked all the fuses. When I turn the key to the on position it makes a little click noise. Then when I try to turn the engine over nothing happens. It also makes a little click noise when I try to trim the motor but nothing happens

 

Tried to jump it and nothing happened. It's an 07 50hp yami 4stroke. I don't have a battery switch on it. So if that leaves me with a loose ground somewhere. The one coming off the battery directly into motor is good. So that puts me under the console. I hope it's not in the control box that looks like a nightmare to take apart. Still don't know what blew the fuse.
Appreciate all your help. Any tips are greatly appreciated.

 

Bad cables or bad connections. I have 12v at the battery and 4v at the motor. I'm thinking bad cables as the connections seem tight. Thanks for all the advice I would of never thought bad cables. Many thanks

 

So I hooked jumper cables between motor and battery. The trim worked fine but motor still wouldn't start. Do you think if it had better connections instead of jumper cables it would start or is there another problem