Originally Posted by ZMan2k2
I've already run it with 1/0 cable. Ive checked my wiring for possible shorts, and it all looks fine. The battery voltage without the truck running is 12.4 volts and ive replaced the factory connectors with beefier ones. Like I said earlier, when at idle, ive seen the voltage go to 11 volts before, and the whole system shuts down. When it reboots, the volume is set lower by the deck automatically, and there are no blown fuses. Im thinking a larger alternator, like 250amps would solve the issue, but im wondering what others think.
Here is the skinny:
At idle, the alternator's output is only capable of 50%. That means that your alternator at idle can only produce 55amps. Alternator rated output is normally at 2000 RPM or higher. So THIS means that for your alternator to put out it's rated 110 amps, your engine will have to be running at 2000 RPM or more.
Since this is NOT the case, the subwoofer amp is drawing the alternator down, and draining power from the battery. (This is why your voltage drops to 11) Many high end or even factory quality stereo systems cannot operate properly at low voltage. In order to protect itself the stereo will power down and reset (Hence your aforementioned lower volume when the stereo "reboots") and this is what you are experiencing.
So what can you do to take care of this problem? There are several options.
- Get a different alternator that is capable of 150amps of output at idle.
- Get a custom pulley for your stock alternator to increase the armature speed. (Hard to find on many vehicles, but they do make them)
- A combination of 1 and 2 where you get a smaller pulley on a better alternator.
- Get a dual alternator setup.
- Don't run your stereo at high bass when idling (Least desireable, but still an option)
Getting an additional battery is like putting a band aid on a gunshot would. It might slow down the bleeding a little, but eventually you will still bleed to death. Now that is not to say running a capacitor or a second battery is not a good idea. It actually is. But to JUST run a capacitor or a second battery is NOT the best idea. Hope my information helped you out.