battery dies every few days
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=109970
Printed Date: April 30, 2024 at 9:30 AM
Topic: battery dies every few days
Posted By: rockyfarted
Subject: battery dies every few days
Date Posted: December 22, 2008 at 10:10 PM
I have a 2001 Ford Mustang GT Convertible and the battery dies after a few days of the car sitting and not being driven. I have recharged the battery a few times now (brand new battery bought a month ago) thought thats what my problem was the first time it happened (cold day dead battery) so I got a new one. So i checked to see if I have anything left on that might be doing it. I thought maybe a light was on but i only have 3 lights, 1 in the trunk and 2 on the rearview mirror all off. I checked with a multimeter by removing the neg cable on the battery and wiring the meter between the - battery and the neg cable and got a 0.80 amp draw. Is that too high for my car? I hear a normal car should be 0.40 amp draw. Am I doing this right? Can someone tell me what's going on here? This started about a month or so ago. I have not done anything to the car recently in the last 8 months thats when I put a new system in it. And has been fine until recently. Could this be an alternator problem? Is the alternator draining down my battery while it's off? But if I drive the car everyday it's fine no battery problems at all. This is not my daily driver but a battery should last a month without having to jump it. My jeep sits for weeks at a time and starts no problem with a stereo system twice the size of the mustang. Anyone here have experience in battery drain problems?
Replies:
Posted By: calijtee1
Date Posted: December 22, 2008 at 10:35 PM
first of all what type of battery did you replace it with, my recomendation kinda pricy but get a dry cell. like a optima yellow top. second check if you have a light in the glove box. my cousin has a roush. had the same problem too. but we found out it was the battery group too small. the way to check it is to disconnect the pos terminal of the battery get a multi meter switch it to amps. put the black lead to the battery cable and the red to the battery post itself check if theres any draw. or you can use a test light also using the same procedure only on the test light the light will light up bright if you got something staying on or low if its kinda normal.
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installers do it best. we got the magic hands!
Posted By: i am an idiot
Date Posted: December 22, 2008 at 10:40 PM
Is there an alarm with starter kill installed in the car?
Posted By: rockyfarted
Date Posted: January 13, 2009 at 2:12 AM
Well still having the same problem now for a while checked most circuits out for drain and nothing more than normal on all of them. (started to pull fuses is how i checked) There is no glovebox light on my car. The only 3 lights there is are 2 in the rearview mirror for when you open the doors to illuminate the interior. The trunk also has a light but that has been removed and not the problem and replaced after checking that. There is no other light on the car. Could this be a drain coming from the alternator? A bad diode in the alternator and pulling power all night to drain the battery. The battery drains so low that nothing works at all. The new battery is one size up from the original biggest I could get for the car when I replaced it.
Posted By: i am an idiot
Date Posted: January 13, 2009 at 5:20 AM
Posted By: i am an idiot
Date Posted: January 13, 2009 at 5:35 AM
Have you tried disconnecting the alternator overnight to see if the battery remains charged? Disconnect the large wire and any plugs that are on the alternator. Oh yeah, I almost forgot, is there an alarm with starter kill installed on the vehicle?
Posted By: sparkie
Date Posted: January 13, 2009 at 8:20 PM
If the reading of 0.8 amps is correct, then you have a major draw on your battery. The generally accepted maximum allowable draw should not exceed 0.05amps. You need to first fully charge the battery by removing it from the car and putting it on a charger. While it is charging insure that your battery cables are clean, tight and no corrosion is present. Clean the battery ground to chassis connection. After the battery is fully charged, re-install it and hook up your digital meter inline to measure current draw. You can hook it up inline on either the positive or negative cable. Deactive the doorpin circuits in the vehicle to allow access to it while you are doing tests. Depending on what type of doorpins you have you may have to unplug them or close the latch inside the door to simulate it being closed. Begin by disconnecting any aftermarket device. Don't just pull fuses for any device as you can cause a feed back problem that can screw up your tests. Unplug all aftermarket modules, relays etc.
Check the reading on the meter each time you unplug something to see if the draw drops. Continue on by pulling each fuse out of the fuse box one at a time until the draw drops. Check the meter after each fuse is pulled. If nothing changes, re-install that fuse and try the next. Continue on with the underhood fuse box. If no change is noted then you need to start tracing the main battery cable. Disconnect anything it connects to such as your alternator. You will only be able to find the problem if you follow a thorough and logical diagnosis procedure. If you are lucky enough to pull a fuse and eliminate the draw, then you need to get hold of schematics to find out exactly which items are on that circuit. If there more than one, then you need to disconnect each one at at time to find the bad one.
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sparky
Posted By: mickeyd063
Date Posted: January 25, 2009 at 9:53 PM
This isnt that helpful of a reply but I have a 2000 Convertible Mustang GT and I'm having similar problems. The only aftermarket thing in it is a new headunit. I got it checked by a shop I trust and they couldnt find any drains and had them put in a new battery since my other one wouldnt hold a charge anymore but I still have the same problem.
Posted By: KPierson
Date Posted: January 25, 2009 at 10:19 PM
I can't believe nobody has asked this yet, but is there an alarm with starter kill installed on the vehicle? As Sparky said anything over 50mA is too much at idle. When you are doing the test it's good to let the car sit for 15+ minutes to make sure all systems go to sleep. I would also disconnect the amp from the battery and see if that changes the reading. It's possible that that the power supply in the added amp has gone bad and is drawing excessive current when the car is off. ------------- Kevin Pierson
Posted By: i am an idiot
Date Posted: January 25, 2009 at 10:25 PM
I AM invisible
Posted By: KPierson
Date Posted: January 25, 2009 at 10:38 PM
haha, maybe me asking will get some answers. ------------- Kevin Pierson
Posted By: rockyfarted
Date Posted: January 26, 2009 at 7:27 AM
I have no aftermarket alarm nor starter kill installed. I have an alarm/starter combo waiting to go into the vehicle when everything gets sorted out and becomes warmer out again but for right now nothing has been touched or installed. I have tried many things to see whats drawing the power from my vehicle battery. Yes I have pulled the fuse near the amp and shut the circuit breaker to the sub amp at the battery. It's an Alpine mrd-m605 in it right now if that helps. Could there be something else thats drawing that much juice from the battery? How can i test the alternator to see if it has a bad diode/regulator? It charges the battery just fine and not making any funny noises. What is the deal with all these mustangs and no one has an answer other than plug it in (trickle charge it) untill I drive it. Thats a band-aid not a real fix. I have read online about many mustangs and no solutions to the same problem. What gives?
Posted By: KPierson
Date Posted: January 26, 2009 at 7:40 AM
I would disconnect the amp wire right at the battery and hook up your meter and disable the doors pins like previously discussed. After 20 minutes start pulling fuses until the current draw drops below 35mA. If you have any aftermarket parts (like a deck) I would start with those fuses first. The ultimate goal is to find a single fuse that the excessive current is being drawn through. Once you identify the fuse you can use a factory service manual to find all devices on that fuse. The next step would be to eliminate the individual devices from the fuse one by one and see which one is pulling the current. I know Nissan had a problem with some of their stock head units going bad and the cd mechanism (I think) would draw a bunch of current even with the car off. This could be something similar. I would agree that a trickle charger is a band aid, but it sure beats the heck out of jumping the car whenever you want to drive it! :) ------------- Kevin Pierson
Posted By: rockyfarted
Date Posted: January 26, 2009 at 8:43 PM
Ok I have door pins but no interior lights It's a convertible so i just pulled the rear-view mirror lead out of the mirror so no lights now. The stereo has been disabled a while ago with no difference. Even power at the battery for the amp has been removed. Terminals are clean at the battery and battery is brand new. Tried pulling fuses but nothing major in a voltage drop seen on the meter. Thats why i'm guessing that maybe it's the alternator drawing juice from the battery after shutdown. Could i just unhook the alternator power leads and check it that way after like a few days and see if it starts after reconnecting the wires back up to it if it does then that would mean the alt is bad right?
Posted By: i am an idiot
Date Posted: January 26, 2009 at 8:48 PM
i am an idiot wrote:
Have you tried disconnecting the alternator overnight to see if the battery remains charged? Disconnect the large wire and any plugs that are on the alternator.
Posted By: chaos7692
Date Posted: January 27, 2009 at 12:57 AM
i am an idiot wrote:
i am an idiot wrote:
Have you tried disconnecting the alternator overnight to see if the battery remains charged? Disconnect the large wire and any plugs that are on the alternator.
you are invisible
Posted By: i am an idiot
Date Posted: January 27, 2009 at 5:08 AM
But wait, YOU can see me. And Kevin sees me too. This is weird.
Posted By: KPierson
Date Posted: January 27, 2009 at 6:04 AM
rockyfarted wrote:
Ok I have door pins but no interior lights It's a convertible so i just pulled the rear-view mirror lead out of the mirror so no lights now. The stereo has been disabled a while ago with no difference. Even power at the battery for the amp has been removed. Terminals are clean at the battery and battery is brand new. Tried pulling fuses but nothing major in a voltage drop seen on the meter. Thats why i'm guessing that maybe it's the alternator drawing juice from the battery after shutdown. Could i just unhook the alternator power leads and check it that way after like a few days and see if it starts after reconnecting the wires back up to it if it does then that would mean the alt is bad right?
There was a specific reason I wrote what I wrote and for the test to work that has been detailed you must follow each step. The door pins may "wake up" the GEM module, so you MUST bypass them, regardless of if it is a convertable or not, or if you have 3,000 different dome lights or no dome lights at all. Dome lights aren't the concern here, electronic modules are. Also, you are NOT looking for voltage drops - you most likely won't see one with an 80mA load. You MUST check current, and you must wait for everything in the car to go to sleep. If you think the alternator may be the cause of the issue you can disconnect the alt while performing the test I mentioned and see if the currend draw goes away. Or, you can just do what you said and unhook it and then hook it back up later - although that seems a bit inconvenient if you already have the proper tools to actually diagnose the problem. You may be best off taking the car to a shop that can run these tests and determine exactly where the draw is. Maybe you should contact I am an Idiot - he usually has some good ideas - I'm surprised he hasn't posted yet. ------------- Kevin Pierson
Posted By: paidnfull
Date Posted: January 28, 2009 at 5:45 PM
i am an idiot wrote:
But wait, YOU can see me. And Kevin sees me too. This is weird.
I think he's avoiding you because of your screenname
Posted By: rockyfarted
Date Posted: January 28, 2009 at 6:27 PM
It's not a 80mA load its an 800mA load that being drawn. As for the door pins I'll just leave the doors open and wait an hour or so and unplug the rear-view mirror lights as to not kill the battery further. I have not had time to recharge the battery yet for further testing. So i'll let the GEM's go to bed and try that first pulling fuses but i tried that before i just pulled them all out and tried it a few days after and the battery was toast. But i'll check again with the multimeter with the modules all sleeping. And then check the alternator after that pull the plug and main + on alt post. Thanks for the help so far guys will let you know when I get the car started and out of the foot of snow right now.
Posted By: stevdart
Date Posted: January 28, 2009 at 9:53 PM
Nice writeup, sparkie! And KPierson. Wasn't anybody else that I could see... ------------- Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.
Posted By: markboss
Date Posted: January 29, 2009 at 9:03 AM
A friend of mine just had a similar problem, we used a voltmeter, and started pulling fuses until we could isolate the circuit... Final solution, was a rear amplifier, for the rear speaker...I understand this is a common problem on these cars...
Posted By: rockyfarted
Date Posted: April 01, 2009 at 1:08 AM
Well finally got around to checking the problem after the winter. Did a few tests and found that one of the rear factory amps power supply had gone bad. Sometimes it would shut off but most of the time it was staying on and drawing power, and thats what was killing the battery. So for the mustang guys out there with the Mach 460 setup check that out for a dead battery problem like i had. So out with the old amps and time for the good ol' oldschool 250 HHCA to go in their place and new speakers.
Posted By: haemphyst
Date Posted: April 01, 2009 at 11:03 AM
I wonder where i am an idiot is to sound off on all of this... He's usually right there with an answer or a very helpful suggestion!
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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."
Posted By: KPierson
Date Posted: April 01, 2009 at 2:16 PM
I haven't seen him post on here for months....
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Kevin Pierson
Posted By: rockyfarted
Date Posted: April 03, 2009 at 1:07 PM
No thanks for the amp's to get fixed they are not worth it they are complete crap. Rather do the aftermarket stuff as I already have it.
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