CenCaliAlum2010

Hey guys I was driving up towards Chico to a buddy's house this weekend and was running my stereo pretty hard most of the way up before i noticed my battery gauge had dropped to 9v. It was 11:30 and I was on 99 in the pitch dark watching my headlights beginning to dim to nothing and then the car started to sputter and I pulled over... Thankfully I have AAA and was able to get it towed back after we tested it to have a bad battery and the alternator was now only pushing 9-10v... one oreilly $115 alternator and a costco battery later and my jeeps back and running!

I'm pretty sure I'm not the only one with an upgraded stereo and a lot are actually pushing more wattage than mine. I got an alpine 500watt rms 4-channel for the 6x9's and door speakers, and an mtx 250watt rms mono block for a single 12". my system can peak at about 1500 watts which i didn't feel was too much. After I replaced both battery and alternator I hooked up a digital voltmeter and was happy to see 12.5v off, and 13.7-14v while running the car. I kept it hooked up and turned up my stereo, the voltage dropped to around 13v. This should be no problem for a battery and alternator to handle I thought? Has anyone else had an issue like this and know how to avoid this happening again? I've done all of the "big 3" upgrades except the larger alternator to battery cable upgrade. Would that be the reason?

CenCaliAlum2010

Any suggestions on whether my stereo was the cause for my alternator going out? Or could it have been just it's time to go? I don't think it's been replaced it a long time, it may have even been original with over 250,000 miles on it...

93gc40

In this situation its not the voltage that matter but the Amperage. You stereo and other electricity using items could be drawing too many amps for your alternator. Stock is about 90 amps (Rated), but if the electical useage is more than that you will damage the alternator or the electrical component. I don't know who much power is require to run just the motor, lights and charge the battery, but it will be pretty close to the output of the stock alternator. So adding things like extra lighting and amplifiers could put you over the Alternator output. You could be using more amps than the alternator can put out and still be getting 12-14 volts.

Dre

I have a 1000w amp and a 450. I also have LED everything... Before that halogen bulbs on everything. Your battery should be 12. Have it tested at Autozone so see if it is bad. You might just have a weak battery. If you want something that is great. Get one of those optimum or orbit batteries. They are stronger.

Posted by: Dre

CenCaliAlum2010

I've heard optima batteries aren't as good as they use to be. I'm running a Kirkland signature series from Costco. I looked up the Kirkland brand batteries online and they actually have a bunch of good reviews. Some boasting them to be better than the wal-mart or sears brands like everlast and diehard.

Unfortunately the xj also takes the smallest battery available from them... Im going to see what it would take to upgrade the brackets and get a larger capacity battery in

RenixHeep

I'm a fan of the diehards, theres a big battery thread on here and lots of people say they like em, its nice to only have one stop at sears for other tools too haha. Shouldn't be too incredibly difficult to do that tho, but you can always relocate it somewhere else and get longer cables custom made from 5-90 on here, sweet cables, I have a set from him, top notch. It's nice to see another person from the central valley on here too, I'm from modesto by MJC.

CenCaliAlum2010

I had a sears die-hard before this and it actually corroded through the top with battery acid and pretty much ruined the battery bracket. So I switched to Costco since I've experienced really good quality products from them in the past I figured this would be the same. I think it's just a case of a small battery that can't handle a large fluctuation of power through running the stereo... And I probably just shouldnt run it on max for a two hour drive to northern Cali :P

Dre

Just don't get the Duralast batteries. When I worked at Autozone, they would fail in extreme heat. To the point it won't hold a charge or had to be replaced on the spot.

Posted by: Dre

91 limited owner

First I would contact Jeep, Asking for the org. build sheet. And see what your jeep came with. Here's the site http://www.jeep.com/wccsapp/universa...ull&category=U They had two alt. options. 90 amp. or 130 amp. Mine came with the 130 amp. (part of the winter pkg. I believe) I have a after market head unit (I run off the fuse box) And a 1400 watt 5 channel amp (I run off the battery) I did just replace my battery, It was a Interstate (cheap 36 month warranty) that lasted 5 years. Most batteries don't last too long over 5 years. I replaced it with a fleet farm (road runner 72 month warranty $60) I believe it doesn't pay to fork out big bucks for batteries, Unless I was living in Alaska.

wildspear

I run after market head unit ( Alpine), sub woofers, amp (hopefully a capcitor soon) and I have not had any problems in the charging area. I believe it was just time for those two items to fail. Geting a better battery and alt will help in the long run expecially if you like to blast the radio a bit and a capacitor will keep some of the strain of your chargeing syestem when you hit the deep bass. So look into a upgrade in the alt department sometime in the future (look in the Junk yard upgrade thread) and maybe think about a cap to run with your amp.

Malik3404

This is simple bro, if you love booming the system there are a few MUST:

- the biggest battery that you can fit (optima or diehard) used both in the past or run a second battery in the back

then add
- big 3 electrical upgrade

if that doesnt work take care of the prob
- bigger altenator

leave the cap's ALONE, back slowly away they just mask the problem

Dre

It's not the battery! When the Jeep is on, it runs off the alternator. The battery just starts the car. Bad battery in a 5 spd... Pop the clutch and u can drive...... Alternator!!! Look for a high output!

Posted by: Dre

mcrilly09

sounds like you should get a capacitor for your amp when i first put mine in every time my subs hit my headlights would dim the capacitor will be charged for your subs alone

Dre

True. I used to have a 1 fared for my amp. Now, I just have a fuse and a $80 battery. Two amps, HID and LED. so, just think of LED and HID to lower the voltage used and tune the amp so it's not a club. Oh, if you have issues starting and the battery is good, check the remote wire. Connect it to a power that is on with accessories or ignition on.

Posted by: Dre

CenCaliAlum2010

my sub is being pushed by a 250watt rms, 500 watt peak mono-block, but I have a 4-channel 500watt rms, 1000-watt peak amp pushing 4 new speakers. I'm not sure which amp is pulling more current, but my lights do dim on hard bass hits. Since the battery and alternator are both under warrantee I think I'll just run it as hard as I'd like to normally and see if it runs it out again. If it does then I'll address it then