Car Stereos: Powering a car amp, self tapping screw, car audio amplifier

Question
Hey, I have a 1999 toyota camry and I was wondering how I would go about getting power to the amp itself? My friend and I have connected everything together except getting the power to the amp. We have grounded it also. We couldn't figure a way to hook in the fuse box or anything.

Answer
Hi Anthony,

The only acceptable method of powering a typical car audio amplifier is to connect the power wire directly to the positive battery terminal.  This means you'll have to find a way to route the power wire through the firewall.  Unfortunately, without having one of these cars in front of me, I can't tell you the easiest way to run the wire.  If you take a look at the area under the driver's side dash, you may be able to see how the factory wiring runs through the firewall.  If the factory wire bundle runs through a large rubber grommet, you may be able to carefully make a small hole in the grommet and route your wire the same way.  You must be very careful not to damage any factory wiring when you're puncturing the rubber grommet.

If you don't find a convenient grommet, you might have to find a bare spot on the firewall and drill your own hole.  I probably don't have to tell you that this is also a potential hazard; you must be very sure that the spot you're drilling is clear of vehicle components on both sides of the firewall.  My favorite trick is to use a self-tapping screw to make a small hole in the location you plan to drill; then you can look to be sure the area is clear before you enlarge the hole with a drill bit.  If you run your wiring through a hole you drilled yourself, you must use a snap bushing or rubber grommet in the opening, so that the power wire doesn't rub against a sharp metal edge.

Generally, there will be a nut on the factory battery terminal that you can remove and use to fasten your power wire, using a ring terminal.  It's very important that you install a fuse and fuse holder on your power wire, as close as possible to the battery terminal connection.

Hope this helps!

Brian