Big 3 made things worse

he probly has same case as me so ill post up to. i tested my alt and batteries and they r both fine. does anyone have any advice if his indeed are NOT the problem?

What size amps, type (class AB or D?), what size alternator and batteries. You both probably just are over taxing your small electrical system. You need a big electrical system to drive a big sound system. Large class AB amps on a small electrical systems will cause the problems described here, and can easily damage your alt or batteries.

 
yea thats what i figured but my voltage stays a about 12.9 to 12.7 at the lowest when im banging on it. i tested it with a dmm and the voltage never went below 12.7 but hte car died if i banged on it at idle for about 2 minutes. so my voltage isnt low but the car dies lol

 
yea thats what i figured but my voltage stays a about 12.9 to 12.7 at the lowest when im banging on it. i tested it with a dmm and the voltage never went below 12.7 but hte car died if i banged on it at idle for about 2 minutes. so my voltage isnt low but the car dies lol
Voltage and amps are two different things. You're drawing more amps than your alternator can supply. Your meter may not indicate very fast voltage drops from the bass notes, but your engine notices the drop. You would have more "boom" in your system if you had enough power to feed them.

 
Make sure all of your connector ends have solid crimped terminals. By simply twisting wires together and taping them, that is a very poor conductor for a high current situation. There just isn't a good enough contact surface between the two and they're prone to move around when the engine is runing/vibrating. Make sure that you've got SOLID 1/0 runs with proper crimped ends going from +ALT to +BAT, -ALT to CHAS. GRND, ENG. GRND to CHAS. GRND, and -BAT to CHAS ground, all grounded in the same spot. Also, what worked for the previous ground might be a tad corroded? Most uni-body cars are spot welded so some body panels (such as the fender maybe) may actually be a poor ground. Find a nice solid piece of the frame to tap into and make sure it's free of paint and corrosion/debris. Your bat might be strong enough to keep the voltage up for awhile but it simply can't supply the current and the alt isn't helping to it's full potential because of poor grounds/connections.

In short, check EVERY connection end. If you don't mind me asking, what are your terminal ends made of, and how did you crimp them on the wires, and how did you go about attaching them to their respective locations. This can tell a lot about the quality of the Big 3 performed.

/end long *** post //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

 
So, you had a taped together connection.... that needs to be fixed properly. Next, you have a voltage problem while idling..... at what rpm are you idling at.... most alternators do not produce current when idling, to me it sounds more like your battery is toast and being drained to supply power to both the car and the system while you are idling. In any case, if the car is fine and the system is fine while the car is moving, the alternator is working just fine.

 
So, you had a taped together connection.... that needs to be fixed properly. Next, you have a voltage problem while idling..... at what rpm are you idling at.... most alternators do not produce current when idling, to me it sounds more like your battery is toast and being drained to supply power to both the car and the system while you are idling. In any case, if the car is fine and the system is fine while the car is moving, the alternator is working just fine.
Right now I'm not using the system since its been acting up. My car idles at 850. Wouldn't the battery read low on the MM?

 
Right now I'm not using the system since its been acting up. My car idles at 850. Wouldn't the battery read low on the MM?
No, because just sitting there at idle with the system off, there is no draw and the battery isn't being sucked dry, so the DMM reading should be fine.

Here's a quick test you can do. Have someone sit in your car controlling the stereo. You should be under the hood with a DMM set to DC voltage. Touch it to the terminals on the battery with the car and system off.

Now start pounding on the system, it should obviously go down..

Now start the car but turn the stereo off and take the reading off the battery. Should be a higher resting voltage now with the car running and the alt spinning (not a ton at idle, but at least a BIT).

Now start the stereo bumping with the car running and note what happens.

Let me know what the readings come out like. On my Honda Accord with a measly *** 90 amp alt (stocker) it rests somewhere in the high 12V but when I start the car, it rests a little over 14V.

It goes down a tad for both readings with the stereo cranked. Should be something atleast somewhat similar for your case. Let me know the results //content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif

 
If the battery is toast, should I get an Optima yellow top? The current battery i have now is a red top and about 6 years old so maybe it was time for a new battery.

 
If the battery is toast' date=' should I get an Optima yellow top? The current battery i have now is a red top and about 6 years old so maybe it was time for a new battery.[/quote']
Red tops are starting batteries not intended for sound systems. You need to add deep cylce batteries, like yellow/blue tops or other deep cycle batteries. If the red top is good, keep it and add deep cycle batteries in the rear. I use a red top up front as a starting battery and a yellow top with a battery isolator so I can run my little system with the engine off for a little while and still have a full starting battery up front.
 
Red tops are starting batteries not intended for sound systems. You need to add deep cylce batteries, like yellow/blue tops or other deep cycle batteries. If the red top is good, keep it and add deep cycle batteries in the rear. I use a red top up front as a starting battery and a yellow top with a battery isolator so I can run my little system with the engine off for a little while and still have a full starting battery up front.
If the battery is bad, what Yellowtop should I go with? I know there's a couple to choose from. I'll be pushing 1500 watts

 
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