Im not very experienced when it comes yo electrical wiring...anyways here is my situation...battery is only like 3 months old...only thing connected to the battery is stereo (po hard wired it to battery...so I take the face plate off when I turn jeep off...) and some hella 500s that are only like half *** wired...(got halfway through wiring them and couldn't find a good ground so I left em...) here is the problem...last night I started the jeep fine...today...all I get is a click...some things inside have power but really weak power...you can tell stereo lost power last night because clock is off...won't take a jump either...where should I start guys

 

Here...i made this just for you
https://www.cherokeeforum.com/f2/non...writeup-71401/

 

Looking like ny battery...can't figure out why though...only 2 months old...however my serpentine is old and loose maybe causing alternator to not charge battery...any ideas on this?

 

New battery in...starts right up...went with a better battery then before so hopefully it'll last

 

Did you have the charging system checked after you installed the battery? Did you tighten the serp belt? Better battery or not, you're going to have the same problem if there is someting wrong with the charging system or have a draw in the system.

 

Brand new serp belt...haven't had the alt checked yet...im pretty sure my serp was causing the battery to go...it was in bad shape...also went from 530 cca to around 600

 

X2 had the same thing happen to me ended up being the smoke lighter cheap and easy fix.

 

The cold cranking amps don't really mean much after the engine is running, that number is only the rated available amp under a load at 0 degrees C.

 

Check the entire charging system. Could be anything from a loose belt, or a bad alternator, to just some loose connection between the alt and battery.

Also check all the grounds from your hella's and stereo. If those are both shoddy work like you seem to be implying, they could be a major drain on your battery, and will kill your new one as well.

 

A cheap digital volt meter is handy all over. If you have high 13 something or 14+ with lights on, you're charging OK. A charged batt. at room temp is 12.7 V. (things like stereo memory, clock, ect might bring that down a tad). As said, the battery is just for starting, most of the power comes from the alternator.

 

I knew it was up, I put it up. I didn't bother saving a link, but people have posted in the thread itself that they found it by searching.

Keywords were "Alternator Starter" checking the title, posts started by "5-90", check all Tech boards.

Search returned in three seconds. There's a very good reason that I put this up on six or seven boards, and I've been hoping that Mods would "stick" it for easier reference for people..

https://www.cherokeeforum.com/f2/bat...or-test-78125/

The answers are out there. I know, because I've put an awful lot of them up there...

 

so im having a problem and could use some help i replaced my alternater and when i turn on the heater it draw alot of power my voltage drops to the last line before the red ...

 

1) Punctuation is your friend - as is spelling (it makes your posts easier to read, and proper spelling helps the next guy when he's searching...)

2) The HVAC blower fan is a fairly large draw - it's typically fused at 30A! If turning on your blower fan (particularly if you turn it on HIGH) is causing your system voltage to drop, you're probably losing generating capacity.

However, it should be noted that the IP voltmeter is a notorious liar, which is why I always try to recommend that any suspect voltage readings are independently verified using a "known good" voltmeter or multimeter before any other troubleshooting is done. Example? My RENIX runs at a nice solid 14.2VDC when it's dinning, and I have far too much alternator (rated at 170A, tested at ~198A. I can jump-start two vehicles at once, and not have any trouble!) However, this 14.2VDC system voltage shows something like 11.5VDC (just under the midway mark) on the IP voltmeter.

Therefore, after getting out the DMM and verifying voltage readings, I reached for the grease pencil and made new marks on the gage window. The voltmeter is now not an "absolute reading" instrument, but a "relative state-of-charge" instrument. The marks may not make sense to anyone else, but I know exactly what they mean and what the needle resting on them would signify - where I have trouble, where things are working fine, ...

This is acceptable until I finally install an accurate voltmeter from a known measuring/sensing point as part of a pending refit.

So, before you do anything else, get out your voltmeter or multimeter and check the actual system voltage from a known sensing point - the best ones to use are either the battery posts or the B+ post on the back of the alternator and a chassis ground or the negative battery post.

 

Well written 5-90. "when it's dinning". I like that. I figured out some of these folk omitting caps. and punctuation aren't necessarily lazy slobs. They are using those gadgets where you just use your thumbs! (probly sometimes sitting in English class!) Don.

PS. Harbor Freight sells a little digital meter for around $5. They actually work/hold up OK. D.

 

OK - I screwed up! It only took me 22 years to learn to type effectively, and I don't catch all of my typos (most of them I do, but some slip...)

If they're not lazy, then they'll have an impetus to write properly. I've gotten to the point where if I have to read a post more than twice to decipher it, I don't answer the thing. Proper writing is not merely for your benefit, but for the benefit of people who read it later (writing is probably the single greatest advantage ever developed by the human race - the extrasomatic storage of knowledge and information allows us to have far more available to us than we can carry around in our heads.)

The Harbour Freight meter is marginally suitable for a "kick-around toolbox" gadget - but if you're going to buy a test instrument, you're really better off spending a bit of money to get a good one - many good multimeters can be had for under $100, quite a few for under $50, and checking with your hardware store, Radio Shack, or electronics supply house will net you a better instrument than you can hope to find at Harbour Freight... You don't need a Fluke or a Beckman, but you can do much better than some Chinese knock-off...