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post #1 of (permalink) Old 01-02-2002, 10:07 PM
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what the $%*#! is killing my battery?

My red top optima will charge up just fine, but if the jeep sits for more than a few days there is significant loss of voltage. If it sits for a week there isn't enough juice to start it. In trying to track down this problem I have replaced the ignition lock cylinder, ignition switch, voltage regulator, and alternator. All of the connections are clean and tight. The battery cables are new 1/0 gauge. I ran new grounds to the engine, frame, firewall, dash, and alternator. Nothing is on in the jeep at night except the alarm, but it does this when the alarm is turned off. Can someone please help.

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post #2 of (permalink) Old 01-02-2002, 10:35 PM
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Re: what the $%*#! is killing my battery?

your profile says a 77 cj7 cool you shouldn't have too much fancy stuff but one trick i learned on older vehicles is to make sure your ign is in the off position, disconnect your ground on your battery. now take a test lite and clamp it to the battery and stick the other end in the battery clamp on the wire so that the lite is now in series. if you got a drain while in the off position the lite will glow. the brightness will tell ya how bad of a drain. somethings you will have to dissconect not just turn off maybe your alarm, fancy digital radios and other nifty stuff that may have memories or require charging when engine is off. i'd dissconnect them with the light is hooked up so you can see what/how they're draining your battery.oh an amp gauge instead of a lite would be more "professional". what you may hafta do after that if you still have a drain is pull one fuse at a time to locate what ckt. it maybe on if that dosen't work it maybe sumthin before the fuse panel. its all a matter of finding it. just an idea

post #3 of (permalink) Old 01-02-2002, 10:41 PM
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Re: what the $%*#! is killing my battery?

The problem ain't all that hard... apply a little logic...

First check out the RedTop... it can still go South on you. Be sure it's good and can hold a charge for a while...

1. Find ALL the circuits, and their fuses.
2. Remove half the fuses and let 'er sit.
3. If the problem still exists, the problem is in the fused circuits.
4. If the problem does not exist, the problem is in the circuits where you pulled the fuses.
5. If the #4 is true, then put in half the reamining fuses and see if the drain occurs.
6. If the drain occurs, the problem is in the circuits where you replaced the fuses in step 5.
7. If the drain does not occur, then put half the remaing pulled fuses back in and let 'er sit again.
8. This is gettin' repetitious... but I think you can see the point.

You're quiclky narrowing down the circuit that has the drain and then once that's done you identify all the devices on the circuit and remove them. If the drain occurs... the problem's in the harness. If the drain does not occur, then replace half the devices back on the circuit... it the same thing you did with the fuses.... only different...

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post #4 of (permalink) Old 01-02-2002, 11:04 PM
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Re: what the $%*#! is killing my battery?

I have the same problem, and have gotten some good advice off the board, but haven't gotten enough free time to actually solve the problem.
Here's a link to the thread...

We both have alarms, and mine is not armed either...I wonder if we should check them first...
What kind of Alarm is yours? Mines an Alpine 8049 or something like that.

Dan 84 CJ-7,Weber,HEI. 95 ZJ,V8. http://www.cableone.net/wdohrn
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post #5 of (permalink) Old 01-03-2002, 01:56 AM
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Re: what the $%*#! is killing my battery?

Thanks for the link. My alarm is a DEI. Not sure of the part number.

post #6 of (permalink) Old 01-03-2002, 02:00 AM
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Re: what the $%*#! is killing my battery?

Thanks Leve, but if nothing is on then how can there be a load that pulls current. I am going to try your advice, but I sure wish I understood electrical theory more.

post #7 of (permalink) Old 01-03-2002, 02:14 AM
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Re: what the $%*#! is killing my battery?

that is pure genious leve
I wish I would have know that in the past

78 CJ7
Spring over 33's
4.3L V6, TH350
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post #8 of (permalink) Old 01-03-2002, 07:31 AM
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Re: what the $%*#! is killing my battery?


You don't have to have anything "on" to get a drain on your battery. A short in a wire somewhere will do the trick for you. You could have a scuffed wire somewhere which is shorting to the body/frame. This will make short work of draining your battery especially if the battery is not in top condition. Once you've found the circuit that causes the drain by using LEVE's method, you will have to run past all the wiring in that particular circuit to find if it is shorting out. You can do that by measuring for continuity to ground in each wire (you will need a decent multi meter for this).

Hope this helps.


'83 CJ-7 in Land Rover Country

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post #9 of (permalink) Old 01-03-2002, 05:29 PM
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Re: what the $%*#! is killing my battery?

He may also have one of the 2.2 million Optima batteries that have the internal defect between the bridges.
Charge the battery, let it sit on the workbench for a week or two with NOTHING hooked to it...
See if the battery holds a charge for a couple of weeks.

(It should hold an acceptable charge for two months or more... That's why they call them 'Storage Batteries')

Testing the vehicle...

Take loose the ground cable(s) from the battery.
Hook in a Digital Volt/ Ohm meter set to DC Volts between the battery negative and the ground cable.
IF you show must millivolts, there isn't much wrong with the vehicle.

If you show 2 or more volts, start pulling fuses and unhooking hardwired components until it goes away, and that will be your culprit.

So many cats, so few recipes...
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post #10 of (permalink) Old 01-05-2002, 08:08 AM
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Re: what the $%*#! is killing my battery?

gosh i thought my idea was too hard to understand until you sorta agreed

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