I'm going to go out on a limb here and guess that you haven't done much car audio install before.
The earth (negative or
) symbol is the return: the (-) versus the (+). In a +12v automotive system, as pretty much every car is, the entire body of the car is connected to the (-) side of the battery. So when it says to connect to earth, negative, ground, or whatever it may be called, it means to either (1) find a wire that is already connected to ground and splice into that, or even better is (2) to find some bare body metal and attach it to that. A good place is usually where something is bolted into the frame of the car. You can undo the bolt, place the wire there, and then replace the bolt for a solid connection.
Pretty much the ONLY line that is ever fused on a +12v automotive electrical diagram is the line supplying power to the device that needs power (that's your #11). The manual is telling you to attach this to the fuse box because they want to be clever and have you wire in a really (technically) nice system that uses the factory fuse box, along with the inline fuse that you have pictured that as #10. This is normally not easy, especially for a beginner, and to be honest, I never do it because then you risk overloading the fuse that you place it on. Car manufacturers use specific fuse values because they tested it with the equipment that they themselves put on that fused line. If you add your equipment to one of these lines, you either risk blowing the fuse by overloading it, or you have to increase the fuse value, and this then becomes dangerous to the rest of the preexisting equipment, because this equipment could now potentially overload and blow before the fuse does.
What's the solution? The clean, and often easier solution, is to run a new line from either the battery itself, or pull a big line from the battery to a power distribution block placed somewhere strategically in the vehicle. Then you can tap off of this. Either way, make sure that you place the fuse as close to the battery or distribution block as possible. This is because the wire could potentially short if it were to touch the body metal, so you want as short a run of wire as possible before the fuse. I learned this the hard way when a wire became stripped in my old car and I had a nice glowing piece of 18 gauge wire that burned through EVERYTHING along the path that the wire took from my battery all the way into my car, UNDER MY FEET, and then into the amp that it was powering. Had there been a fuse at the battery, it would have just blown and would have saved me quite a bit of damage. And yes, I was driving at the time. And yes, I FREAKED out...
Linear Mode
