Common places voltage can 'leak'...

[Eric VerValin]

OK... well this has been a semi on going thing.. and I'm starting to think its an intermittent problem.

My car still for some reason after sitting for a few days wants to **** my battery. The multimeter I have now, has an automatic "range" adjustment and its kind of a pain to see a voltage drop on such a small scale. My question is this...

For anyone who has diagnosed something similar.. what kind of voltage drop did you find? How much will **** a battery in 3 days?

I have the largest battery I can get in there.. 700+ CCA's, not even a month old. New wires, new connectors, new power wire to the fuses under the hood even. Starter was just rebuilt, alternator probally has 25K on the rebuild. The only thing I can think of is my car alarm. I pulled the bulb from under the hood, and the one in the trunk turns off like it should, and I'm just running out of things to check. The only other "odd" thing that might have something to do with it is that on occassion when I open the door, its already "chiming" at me like I have a key in it. Always thought that was strange, but oh well... Maybe the "key in ignition" module is eating up my voltage?

Its just sad that I have to jump it after 3 days, and my truck has sat still since... hmmm November, and fired right up..



Edit : Found a post stating that 100ma was "more than enough" of a drain with the car off... I'm assuming I should add a little for my car alarm? Even tho its off, its still feeding that little LED and the reciever for my key fob.. so I would think that would draw a little bit.

 

[SHOZ123]

Going to have to hook up the volt meter and use the amp reading part of it. You should have about a 50 mA draw if all is good. Anything higher and it is not suppose to be there and will speed up the battery discharge.

Connect the amp meter and start pulling fuses until you track down the circuit that is drawing too much current.

 

[firstgen89sho]

it might be your ignition cylinder, it is probably worn out and you are turning it back into accessory position. I have had a Taurus come into work with the similar problem kept killing battery, well the ignition cylinder was worn out and you could pull the key out while the key was in any position.

Just some food for thought. all my cars have new lock cylinders in them for that reason.

 

[Eric VerValin]

... hmmm good one to check.. didn't consider that... I know i've replaced the key cylinder, but that was back in ummm... 1999 something like that.. I know its been on/off about a million times since then...

I think that'll be the first thing I check..

 

[Devin]

Check your alt. I had a brand new alternator and the car did nothing but sit for four months. I charged it overnight to make sure it'd work and test drove it. It worked fine! The next day my wife drove it about three miles and it quit.

The reasoning is that the alt would sometimes put out 16v, 13v, 12v and even 10.5v and the car would randomly stop charging. I checked it by running some speaker cable under the clamps, out the hood and in the passenger side window and having my voltmeter hooked up to it reading it while I drove.

 

[Storm-Chaser]

Think about it - what ever is on that circuit that powers the door chime when you open the door, is potential getting power as if the circuit is wired HOT at all TIMES. Components that would normally only be powered in which ever position it's stopping in (HOT in ACC / HOT in RUN) will be continuously drawing power.

 

[itwonder]

You can use milliamp function on your meter, connecting the meter in series between the + battery terminal and the + battery cable. Pull fuses and see if the current draw goes away.

 

[NotSoSlowSHO]

Id check the under-hood, trunk, and glove-box lights first. Chances are, one of the switches for these circuits are bad

 

[firstgen89sho]

thing is tho, is if the battery is being drained within a couple days, there has to be at least a good half an amp to an amp draw, if not more.

 

[SHOZ123]

True on that. I had a .68A extra draw on mine and it would drain the battery in 3-4 days of non use. Quite a bit more than the 50 mA.

 

[Eric VerValin]

thing is tho, is if the battery is being drained within a couple days, there has to be at least a good half an amp to an amp draw, if not more.

Ok.. riddle me this... I got my meter on there, and got .05 Amps... now what? lol

 

[hawkeye18]

Light switches won't cause the battery to die as the car turns all lights off after 45 minutes... I believe this is a function of the RKEM. The ford engineers designed this to save your battery, and I know it's saved mine quite a few times!

+1 on doing the series current check and pulling fuses. Start with engine compartment fuses, and work your way down into the cabin fuses if that's where it leads you.

PLEASE PLEASE do NOT hook your amp-meter between the POSITIVE and NEGATIVE leads on the battery. You will arc-weld the leads, terminals, and quite possibly you, and you will **** the battery. Make sure you touch both leads to the positive side of the battery. Just sayin'. I've seen three too many people do this. One of them being my wife .

 

[Eric VerValin]

What I enjoy is holding one end, putting the other lead on the + and slowly touch and apply pressure to the negative terminal, and you can watch the voltage go up.. lol Anyway... in THIS post, the "normal" draw was 500mA.. isn't that .05 A ?

 

[NotSoSlowSHO]

Light switches won't cause the battery to die as the car turns all lights off after 45 minutes... I believe this is a function of the RKEM. The ford engineers designed this to save your battery, and I know it's saved mine quite a few times!

Eh.... What??

Ive NEVER heard of this? Any proof?


I know for a FACT that the RKEM doesnt cut power to the in cabin fuse panel after 45 minutes. My wife has left cabin lights, as well as the glove box open before, and the power stays on, till there isnt any more

The switches I am referring to cut power to the glove box light, under hood light, and in trunk light when they are shut. If they fail, and they DO, the light will remain on.

 

[Shoaz]

What I enjoy is holding one end, putting the other lead on the + and slowly touch and apply pressure to the negative terminal, and you can watch the voltage go up.. lol Anyway... in THIS post, the "normal" draw was 500mA.. isn't that .05 A ?

No, 0.5A is 500mA. 0.05A is 50mA.

Be careful with the ammeter that it's in a range where overcurrent isn't going to **** it.

 

[firstgen89sho]

the amperage draw is right.

There is no such thing as the lights turning off after 45 minutes, 96 and newer cars had that on the GEM. but the older cars never had that option.

 

[93MTXSHO_STUD]

I have some experience with battery related issues... I used to go through batteries really quickly for 2 reasons... 1) crappy alternator would overcurrent/charge my battery. 2) I bought crappy walmart batteries. More recently, before my starter went out everytime I would crank it, it would barely start being the starter was shorting out pulling many amps from the battery (shorting battery life). Make sure you test current draw in series with the battery. I would think a safe static current draw should be less than 100mA. I think mentioned in this thread, to really isolate a problem, pull out each fuse (start with the easy ones in the engine bay, then work your way to the ones by the steering wheel and measure the series current draw on the battery. My problem went away when I purchased a reman alternator. If you are getting less 100mA of static current draw, more than likely its your alternator.

 

[Eric VerValin]

Well.. let me ask this then.. Because I had my alt load tested, and supposedly its ok. But with my UDP's, I know at idle, I'm probally going to be below what I should be putting out. Just like yesterday.. it was dead as a doornail, and after a jump and a 10 minuite drive it was fine. Let it sit for a few hours, and it started right up again.

I'll call my guy and see if he's got parts for this alternator, and get it rebuilt again just for kicks and see if that solves it, because like I said a few posts ago, I'm only getting / reading 50ma draw with everything off, which should be 'normal' right? I think I'll pull the radio fuse just to see.


And also.. with batteries... aren't they all kind of the same? I mean the same place makes DieHard's / Advanced Auto batteries / Autozone batteries... wouldn't they make the same ones for Wal-Mart too? Just a few plates of lead and some acid right? I could be wrong... have been before..


Another thing... my positive terminal on the battery is awful close to the hood. So close it dents the under hood blanket. Maybe I'm losing a little there? Its not touching steel.. but it sure is pretty close.

 

[Eric VerValin]

Jumped it yesterday, drove 10 miles. Off for 4 hours, on again 10 more miles. Off all night, dead as a door nail. I don't have the patience right this minuite, plus its pretty cold outside, and I'd rather be a big baby and pout about it for a while and drink some coffee before I go mess with it again.

Without disconnecting anything, I put my meter on it after I jumped it last time and tried to check the voltage.... 12.7... and... if I sit there and hold it.. I can watch it bleed off... 12.69... 12.68... 12.67.. I stopped @ 12.45.. assumed it continues.

I guess I could / should just take it in to get it load tested.. even tho its new, but.. my amperage readings are "OK" ?

I did get a chance to polish up the engine bay a bit while I pondered these things.. then came back inside for coffee... I'm still 1/2 asleep..

 

[itwonder]

Simple test: Disconnect battery, wait overnight, reconnect. Does it start?