How do you install a battery in the trunk for your car audio system I have a Deep cycle battey and want to run my amp off it (400rms) would it be like :
1. + from battery to amp 2. - from battery to amp
if the it is wired like this it's almost like self charging right or would I have to run a + wire from car battery to battery in trunk. CAn someone clear this up for me give me a step by step list.
well, usually u want both batteries to be 'drycells'.
secondly, You need to do a positive run from the front battery to the back battery(ies). Then a positive run from the back battery to the amp (short run).
After this, ground all batteries to the chassis and groud the amp also to the chassis.
Do you think I could do this with a stock Alt or will it eventually kill 1 or both batteries I drive a Saturn SL2 and would the trunk battery pull from the front battery causing the front to die
If you're still running on the original stock alternator, then it'd be a good idea to install an isolator. The odds are, your battery and alternator will die soon. That's just how it goes. All things die after prolonged usage.
In an older cars with original battery and alternator, an isolator can be very useful. For example, if your starter dies, you can use the aux battery to start it using a jumper cable. Because it's isolated from the starter, it won't get drained. After 125k of miles, there's high probability that it will go soon. Nothing like having a backup. There's also no need to replace the starter battery either. If it's working then use it. We don't need to pollute the landfill any further.
There are signs that your alternator or battery is dying or near death and they're fairly simple to notice before it gets to the point of where you're stranded.It happens to people that know nothing about cars all the time though or are just not very observant.
Rob, your statements are not accurate. As I have mentioned before, a voltmeter alone is not enough to determine the state of a battery/alternator. It has nothing to do with being a noob either. For someone with experience, you sure say lot of irratic statements.
Since you sound like an expert on battery and alternator symtoms, let me give you an example. If in your car, a voltmeter showed 12.5v - 12.9v with engine off, 13.2v - 14.4v with engine on, no problem starting. It would then randomly show 13v - 14v once every 7 - 10 days. What do you think is the issue? Please state how you could detect "clear signs" using your methods. I'm sure all the noobs are dying to know.
with only 400wrms your problably better off just putting the deep cycle battery up front replacing your old one.
If you want do a big 3 with 4 gauge wire, and run a good 4 gauge wire from you batt back to the amp.
if your really worried get a new OEM alt for your car... should cost about 100 bucks. then with the deep cycle batt you should have no worries with 400 watts.
"What do you think is the issue? Please state how you could detect "clear signs" using your methods. I'm sure all the noobs are dying to know."
A good charging system is consistent.When there are fluctuactions as described above there's obviously a problem.Like I said Isaac they're easily noticeable but then again...people these days would probably be negligent on something like that,half the people out there run their cars into the ground,not maintaining them at all and not being responsible as a motorist.Then they're there on the side of the road stranded when that could have been avoided most of the time.
Rob, the example I gave you, is not clearly detectable. That fluctuation could be caused by the amp/heater or anything else that sucks up lot of current. So for most people, there is no way they can tell if it's battery/alternator/ground/cable/short problem. You can measure the voltage everywhere, and it'll always show the correct reading. FYI, the problem was with alternator. It produced the voltage under normal condition, meaning driving, braking and starting. However, if you applied anything that used up lot of current (20A - 30A), it dropped voltage to 12.5v. This is something you can't "monitor" nor guess. It's easy to say that problems like this only happen to noobs, but as you can see, even the pros would've had tough time figuring out. Voltage alone is not the solution, nor a great indicator.
"FYI, the problem was with alternator. It produced the voltage under normal condition, meaning driving, braking and starting. It's easy to say that problems like this only happen to noobs, but as you can see, even the pros would've had tough time figuring out. Voltage alone is not the solution, nor a great indicator."
That wasn't very clear to me Isaac.Especially the following part:
"However, if you applied anything that used up lot of current (20A - 30A), it dropped voltage to 12.5v. This is something you can't "monitor" nor guess."
Actually...you could easily see what's causing the fluctuations if that was the case.If your voltage is dropping or lights are dimming upon peak times in music through the car audio system then you obviously need a stronger alt but I'm not too sure on what you were saying so...It's funny how we always get into these debates because you recommend what I think is somewhat useless in a car audio system and that's an isolator.If you run your batts to the point of where they're dead you more than likely damage either A-The amplifier or B-The subwoofer(s).
how about you run a charging system test and then you'll know wtf is wrong. i agree though, there isn't always signs of a alternator about to sh!t out on you. sometimes its apparent but other times it just craps out.
Rob, I gave you all the "signs" that occured. What I didn't tell you right away were the "answers." I never tried to argue with you in the first place. Look at all my posts. It was you contradicting me on everything. So I replied back saying, you can't blame noobs for all the problems, AND sometimes, it's just not possible to detect faults just by "monitoring" voltages. I'm not on here to put down people nor start fights. I only correct or say my 2 cents worth, when people post that's not true or way off topic. Before you take it the wrong way, read my posts carefully. When people face problems, they don't have the options of knowing the solution before hand. The scenario I described, is perfectly legit. That is why I asked you HOW you would've solved/diagnosed it using your methods. After all, it's not the first time you said "they're fairly simple to notice " and "It happens to people that know nothing about cars all the time."
I'm saying that's not true. It can happen to anyone.
