2008 Mustang Battery Drain Issue
12/3/11, 09:36 PM
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2008 Mustang Battery Drain Issue
Okay, so I have done a little research and found very similar problem to my own, but haven't found a single clear solution. Hoping that maybe if I ask myself, maybe I'll get lucky.
I started experiencing problems with my battery about a year ago (about 2 years after purchasing). It was unfortunate but the testing results proved the battery to be going downhill. I replaced my stock battery with an Optima battery and all was good for about 6-7 months, and then crap began to roll downhill.
I drove about 400 miles in a day (a 200 mile trip that was back to back), which is normally not a big deal. Very next morning, my battery was dead (it wouldn't even turn over). I had to walk to work but had a friend jump my car for me, so all was good at that point. A couple days later (approximately 2 days), I drove 200 miles and noticed that my AC fan wasn't working right... now, this (I don't think) isn't related to the battery drain, but it was the beginning of the end. The cold air was seeping through the vents and I could hear the fan blowing but no air was being pushed through the vents. It was very bizare. When I was parked, I opened the hood to check it out and noticed my AC pipes were frozen SOLID. Almost a half an inch in thickness. I could hear the ice melting and by the time I drove another 40 minutes and parked my car for the night, the ice was melted and everything seemed to work (fan and AC alike).
Next morning, my car wouldn't start. I had scheduled an oil change at Titus Will Ford dealership--I live in another state and have no real good mechanics to take it to yet, so I wanted a dealership to check out the standard checks. I told them about the battery issues and had them check it and test it for me. My battery checked out perfectly fine. It was recommended by the mechanic that I install a new battery--because with Optima's it is hard to tell if there's a bad/dead cell in the battery and that could be the problem. I took that advice--because I need my baby to work!--and went out and bought another battery (about $100, ugh). Everything worked well for about 2 days when suddenly, I went to start my car to return home to Oregon and the car was dead.
I jumped the car and brought it back to the dealership to get it checked out. The dealership ended up holding onto my vehicle for almost an entire business week, unable to precisely locate the problem. In the end, they told me they were positive that my alternator was the draw on my battery (seems ridiculous, but they were convinced). I had them replace the alternator and once again, problem solved for another 2 days... And it was dead again.
I brought it right back to the dealership, infuriated by this point (alternator was $500 + $100 battery = $600 in and no results). The dealership continued a cat and mouse game of 'what in the world is the problem?' and held onto my car for almost two weeks. I finally got an answer that my radio was the draw, that it was shorted and not turning off. Funny thing is, the radio had no issues before I brought it into the dealership and now it's shorted... whatever. If that was the problem, I told them to disconnect the fuse to the radio. I was told that as long as I unplug that fuse every time I'm done using the radio when I drive, my battery won't be drained.
This worked for several weeks. Problem solved...right? About a week ago, I drove my car another 200 miles and it wouldn't start the next morning. Figured it was a lose terminal connection (which, it was loose) and left it at that. However, today I went to my car and it wouldn't start. Completely dead again--won't even turn over. The radio fuse has been unplugged for several days. I went on a fuse hunt today--using a tester--and unplugged one fuse at a time to see which was still drawing on my battery... Found nothing. But there is a draw and I can't figure out what it is or why.
Anyone else experiencing this problem? Any suggestions? Ideas? This is driving me crazy.
2008 Ford Mustang > v6, automatic > Shaker 500 Sound system, Pony Package (with all that fun stuff)
I started experiencing problems with my battery about a year ago (about 2 years after purchasing). It was unfortunate but the testing results proved the battery to be going downhill. I replaced my stock battery with an Optima battery and all was good for about 6-7 months, and then crap began to roll downhill.
I drove about 400 miles in a day (a 200 mile trip that was back to back), which is normally not a big deal. Very next morning, my battery was dead (it wouldn't even turn over). I had to walk to work but had a friend jump my car for me, so all was good at that point. A couple days later (approximately 2 days), I drove 200 miles and noticed that my AC fan wasn't working right... now, this (I don't think) isn't related to the battery drain, but it was the beginning of the end. The cold air was seeping through the vents and I could hear the fan blowing but no air was being pushed through the vents. It was very bizare. When I was parked, I opened the hood to check it out and noticed my AC pipes were frozen SOLID. Almost a half an inch in thickness. I could hear the ice melting and by the time I drove another 40 minutes and parked my car for the night, the ice was melted and everything seemed to work (fan and AC alike).
Next morning, my car wouldn't start. I had scheduled an oil change at Titus Will Ford dealership--I live in another state and have no real good mechanics to take it to yet, so I wanted a dealership to check out the standard checks. I told them about the battery issues and had them check it and test it for me. My battery checked out perfectly fine. It was recommended by the mechanic that I install a new battery--because with Optima's it is hard to tell if there's a bad/dead cell in the battery and that could be the problem. I took that advice--because I need my baby to work!--and went out and bought another battery (about $100, ugh). Everything worked well for about 2 days when suddenly, I went to start my car to return home to Oregon and the car was dead.
I jumped the car and brought it back to the dealership to get it checked out. The dealership ended up holding onto my vehicle for almost an entire business week, unable to precisely locate the problem. In the end, they told me they were positive that my alternator was the draw on my battery (seems ridiculous, but they were convinced). I had them replace the alternator and once again, problem solved for another 2 days... And it was dead again.
I brought it right back to the dealership, infuriated by this point (alternator was $500 + $100 battery = $600 in and no results). The dealership continued a cat and mouse game of 'what in the world is the problem?' and held onto my car for almost two weeks. I finally got an answer that my radio was the draw, that it was shorted and not turning off. Funny thing is, the radio had no issues before I brought it into the dealership and now it's shorted... whatever. If that was the problem, I told them to disconnect the fuse to the radio. I was told that as long as I unplug that fuse every time I'm done using the radio when I drive, my battery won't be drained.
This worked for several weeks. Problem solved...right? About a week ago, I drove my car another 200 miles and it wouldn't start the next morning. Figured it was a lose terminal connection (which, it was loose) and left it at that. However, today I went to my car and it wouldn't start. Completely dead again--won't even turn over. The radio fuse has been unplugged for several days. I went on a fuse hunt today--using a tester--and unplugged one fuse at a time to see which was still drawing on my battery... Found nothing. But there is a draw and I can't figure out what it is or why.
Anyone else experiencing this problem? Any suggestions? Ideas? This is driving me crazy.
2008 Ford Mustang > v6, automatic > Shaker 500 Sound system, Pony Package (with all that fun stuff)
12/3/11, 10:13 PM
#2
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Man. You have a real bugaboo.
If you want to know what the real cause is, you'll have to do the legwork. Here's how.
First, make sure the battery is *fully charged*. This is all for nothing without that.
Next, disconnect the negative terminal of the battery, and for the duration of this test, that terminal is never to be connected to the battery again.
Next, you will need a multimeter, preferrably digital, set to DC Amps. You will basically insert it between the negative battery cable and the negative battery post, allowing the multimeter to complete the negative connection.
Now, the fun part. Note the draw on the battery. Now start pulling fuses and relays, both under the hood, and in the passenger compartment. Each time you pull a fuse, the draw must be checked. Make *complete* notes. Each fuse you pull, note the change, or even lack thereof, in draw.
You will quickly find the large draw, if there is one, when it stops drawing. That fuse, and it's accessories it protects, is the one that needs attention.
You may find this doesn't show up unless the car is running. This should probably not be the case, given your symptoms, but it is still possible. BUT, if that's the case, then the alternator is the most likely culprit, and it is ENTIRELY possible that the alternator you had them replace happened to also be bad.
Now, normally, this draw, with the key off, engine off, should be somewhere about 30-50 milliamps*. (shown as 0.050 or similar on the display), and certainly nothing over 1 amp (1000 milliamps) (1.000 on the display).
If the draw is over 10 amps, or whatever the max is for the multimeter, there is usually a fuse or protection circuit in the multimeter to prevent it from blowin' up. If you have that big a draw, man, you have *issues*, to say the least. I'm sayin' if you have something like 500mA or more, you're looking at something wrong as well.
If you do have this, then the fuse removals will quickly enough point out what's goin' wrong, and you can attack that pretty easily. Say, you pull the fuse for the blower motor, and the draw jumps from .560 to .040, then you've probably found the thing, but it could be the motor, the wires, the connectors, or the SJB.
That is pretty much the only way you're going to find it out. I don't envy you. I do wish you luck.
/ *-This is a guess, based on another thread in another place when checking this out for procedural correctness to prevent memory error induced posting, as to what the key off, engine off draw is. I do not actually know what a shaker 500, active anti theft, fully-goodied out, but stock Mustang, whether V6 or GT, would draw at key off, engine off, but I'm hopeful it's not over 500mA...?
//I should probably know... meh.
If you want to know what the real cause is, you'll have to do the legwork. Here's how.
First, make sure the battery is *fully charged*. This is all for nothing without that.
Next, disconnect the negative terminal of the battery, and for the duration of this test, that terminal is never to be connected to the battery again.
Next, you will need a multimeter, preferrably digital, set to DC Amps. You will basically insert it between the negative battery cable and the negative battery post, allowing the multimeter to complete the negative connection.
Now, the fun part. Note the draw on the battery. Now start pulling fuses and relays, both under the hood, and in the passenger compartment. Each time you pull a fuse, the draw must be checked. Make *complete* notes. Each fuse you pull, note the change, or even lack thereof, in draw.
You will quickly find the large draw, if there is one, when it stops drawing. That fuse, and it's accessories it protects, is the one that needs attention.
You may find this doesn't show up unless the car is running. This should probably not be the case, given your symptoms, but it is still possible. BUT, if that's the case, then the alternator is the most likely culprit, and it is ENTIRELY possible that the alternator you had them replace happened to also be bad.
Now, normally, this draw, with the key off, engine off, should be somewhere about 30-50 milliamps*. (shown as 0.050 or similar on the display), and certainly nothing over 1 amp (1000 milliamps) (1.000 on the display).
If the draw is over 10 amps, or whatever the max is for the multimeter, there is usually a fuse or protection circuit in the multimeter to prevent it from blowin' up. If you have that big a draw, man, you have *issues*, to say the least. I'm sayin' if you have something like 500mA or more, you're looking at something wrong as well.
If you do have this, then the fuse removals will quickly enough point out what's goin' wrong, and you can attack that pretty easily. Say, you pull the fuse for the blower motor, and the draw jumps from .560 to .040, then you've probably found the thing, but it could be the motor, the wires, the connectors, or the SJB.
That is pretty much the only way you're going to find it out. I don't envy you. I do wish you luck.
/ *-This is a guess, based on another thread in another place when checking this out for procedural correctness to prevent memory error induced posting, as to what the key off, engine off draw is. I do not actually know what a shaker 500, active anti theft, fully-goodied out, but stock Mustang, whether V6 or GT, would draw at key off, engine off, but I'm hopeful it's not over 500mA...?
//I should probably know... meh.
Last edited by houtex; 12/3/11 at 10:19 PM.
12/3/11, 10:38 PM
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@houtex
That is actually what I did today. I don't have a multimeter, but did use a circuit tester--it would light up if there was a draw on my battery. So I went through most of the fuses (save a few that I couldn't quite get out with the tools I had on hand) and didn't find the significant draw. EDIT: There IS a draw, the light was definitly lit the entire time I was pulling fuses... but I couldn't find the fuse that ended the draw.
I am worried about the alternator... The one that I got replaced was actually refurbished (which I was unaware of). Perhaps I just got two lemons instead of working alternators?
That is actually what I did today. I don't have a multimeter, but did use a circuit tester--it would light up if there was a draw on my battery. So I went through most of the fuses (save a few that I couldn't quite get out with the tools I had on hand) and didn't find the significant draw. EDIT: There IS a draw, the light was definitly lit the entire time I was pulling fuses... but I couldn't find the fuse that ended the draw.
I am worried about the alternator... The one that I got replaced was actually refurbished (which I was unaware of). Perhaps I just got two lemons instead of working alternators?
12/4/11, 05:53 PM
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Yeah, it's sort of possible that's what happened on the alternators. They're made by humans, after all, and humans are anything but infallable. 
IMO, the light test isn't any good. It's light doesn't take much to get lit on amps. You can't find significant draw, or a drop in draw, just that there's draw. You really should get a multimeter. But I'll let you decide on that.
IMO, the light test isn't any good. It's light doesn't take much to get lit on amps. You can't find significant draw, or a drop in draw, just that there's draw. You really should get a multimeter. But I'll let you decide on that.
12/5/11, 07:56 AM
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I started experiencing problems with my battery about a year ago (about 2 years after purchasing). It was unfortunate but the testing results proved the battery to be going downhill. I replaced my stock battery with an Optima battery and all was good for about 6-7 months, and then crap began to roll downhill.
I drove about 400 miles in a day (a 200 mile trip that was back to back), which is normally not a big deal. Very next morning, my battery was dead (it wouldn't even turn over). I had to walk to work but had a friend jump my car for me, so all was good at that point. A couple days later (approximately 2 days), I drove 200 miles and noticed that my AC fan wasn't working right... now, this (I don't think) isn't related to the battery drain, but it was the beginning of the end. The cold air was seeping through the vents and I could hear the fan blowing but no air was being pushed through the vents. It was very bizare. When I was parked, I opened the hood to check it out and noticed my AC pipes were frozen SOLID. Almost a half an inch in thickness. I could hear the ice melting and by the time I drove another 40 minutes and parked my car for the night, the ice was melted and everything seemed to work (fan and AC alike).
I drove about 400 miles in a day (a 200 mile trip that was back to back), which is normally not a big deal. Very next morning, my battery was dead (it wouldn't even turn over). I had to walk to work but had a friend jump my car for me, so all was good at that point. A couple days later (approximately 2 days), I drove 200 miles and noticed that my AC fan wasn't working right... now, this (I don't think) isn't related to the battery drain, but it was the beginning of the end. The cold air was seeping through the vents and I could hear the fan blowing but no air was being pushed through the vents. It was very bizare. When I was parked, I opened the hood to check it out and noticed my AC pipes were frozen SOLID. Almost a half an inch in thickness. I could hear the ice melting and by the time I drove another 40 minutes and parked my car for the night, the ice was melted and everything seemed to work (fan and AC alike).
Welcome to the forum! My name is Deysha with Ford Customer Service. I recommend you another appointment with your Ford dealer and have your vehicle diagnosed. Your Service Manager will be in the best position to assist you with this. Also, Please PM me with your VIN, mileage, contact info, and dealer so I can look into this further for you.
Deysha
7/24/12, 07:06 AM
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And you guys are not alone. I am waiting now for AAA to show up for a jump. Then I will drive to the dealership and have them put in battery #5.
I took delivery Sept. '05, I replaced the original factory battery in '07, then another in '09, then the latest in March '10. Sixteen months is about as far as they go before failure. I keep going back because they're replacing at no charge.
I took delivery Sept. '05, I replaced the original factory battery in '07, then another in '09, then the latest in March '10. Sixteen months is about as far as they go before failure. I keep going back because they're replacing at no charge.
7/24/12, 09:47 AM
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This time I have received a different diagnosis. The shop says the alternator has failed and they are going to replace it.
Only time will tell if this is a resolution or not.
Only time will tell if this is a resolution or not.
7/25/12, 10:19 AM
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This is a pretty common problem that's been around forever, and I've never found/read any fix for it. At this point, I think it'd be a waste of money to even have someone try to find the problem. All I can say is don't spend too much money on a battery/alternator cuz a "better" one isn't gonna fix it, and get the longest warranty you can find. If you don't have another car at home to jump with, I'd also look into getting a charger.
7/25/12, 11:32 AM
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This is so random. Mine has been great - even sitting in the garage for 5 months of winter and only firing up every 4-5 weeks. And its 4 1/2 yrs now.
I always wonder if the alarm is a drain on some vehicles. Maybe the motion detector or other sensors? When mine is garaged I do not arm it.
I always wonder if the alarm is a drain on some vehicles. Maybe the motion detector or other sensors? When mine is garaged I do not arm it.
7/25/12, 11:37 AM
#11
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That's how mine was; lasted three+ years even with added electronics and it never failed. But like yours Charlie it sat in the garage without the alarm on, through the winter season. In spring, it would fire right up. No tender, no nothing.
7/26/12, 08:56 AM
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Indicators on the charger were normal during charge, then it went into maintenance mode. But after 10 hours it did not indicate the charge cycle was complete.
1/14/14, 06:53 PM
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I also have a 2008 Mustang gt and had battery problems. Theres a leak in the fire wall on the right side which sends water down on top of the fuse panel and circuit board that is in the passenger kick panel. Ford has said this is not covered under warrenty yet they have issued a service bulliten on how to fix the problem. If as in my case they have to replace this panel it's like $2500
I have and extended warrenty and they siad it wasn't covered I was luckey to have a great service manager
I have and extended warrenty and they siad it wasn't covered I was luckey to have a great service manager
1/16/14, 02:32 PM
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I also have a 2008 Mustang gt and had battery problems. Theres a leak in the fire wall on the right side which sends water down on top of the fuse panel and circuit board that is in the passenger kick panel. Ford has said this is not covered under warrenty yet they have issued a service bulliten on how to fix the problem. If as in my case they have to replace this panel it's like $2500
I have and extended warrenty and they siad it wasn't covered I was luckey to have a great service manager
I have and extended warrenty and they siad it wasn't covered I was luckey to have a great service manager
My name is Deysha with Ford Service. Glad to learn your dealer helped you out with this! A TSB is a repair procedure sent to our dealers in case someone comes in with a specific concern. It is not a Recall and it’s only covered under your new-vehicle limited warranty.
As you are witness, your service manager is in the best position to let you know if there is work needed, and about coverage you may have for it (warranty, recall, etc.), or any assistance available. Also, remember repairs done at a Ford Dealer come with a 24 months/unlimited miles warranty.
Deysha
1/18/14, 04:06 PM
#15
Anything ever on having a 2007 GT/CS as well as GT's about how Ford cannot get paint to stick to the hood ? Mines been redone once & it's back with a vengance , the way I see it , I don't think the hood is nor was grounded at all not the aluminum treated or preped right.
You never see this on airplanes or Grumman trucks , so why does my Ford service tech tell me to bad for me .
You never see this on airplanes or Grumman trucks , so why does my Ford service tech tell me to bad for me .
4/2/14, 06:15 PM
#16
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I think mine is a similar problem. I have an 08 Bullitt with the Mach 1000 and noticed during this long and nasty winter that my battery was going bad and then eventually died. I noticed my factory radio cd player would sound like its cycling, trying to find a cd when I unlocked the car and opened the door and hear the noise it makes. After replacing the dead battery the radio still does the same the thing and I'm afraid its going to kill this new battery..please I need help.
Last edited by 08Bullittman; 4/3/14 at 02:59 PM.
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4/8/14, 08:42 AM
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I have had the battery drain issue with my 2005 GT since I bought it in November 2004. Had the dealer check it numerous times over the years. Most recently this past January I had my local garage check it. No one has ever found the drain.
I have a new Optima redtop battery and still have the drain, so i keep the car on a Battery Tender trickle charger. I decided to pull the Shaker 500 main fuse from under the hood and left the car off the charger for 7 days and it started up no problem. It has not been on the charger for a month now and till no problem. I am now convinced that the factory Shaker 500 radio and amps are causing the problem. I would rather the car start than listen to the radio.
Anyone know if I were to put in an after market unit will I have to use the factory amps or can I bypass them?
I have a new Optima redtop battery and still have the drain, so i keep the car on a Battery Tender trickle charger. I decided to pull the Shaker 500 main fuse from under the hood and left the car off the charger for 7 days and it started up no problem. It has not been on the charger for a month now and till no problem. I am now convinced that the factory Shaker 500 radio and amps are causing the problem. I would rather the car start than listen to the radio.
Anyone know if I were to put in an after market unit will I have to use the factory amps or can I bypass them?
3/3/15, 07:25 PM
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Same ussue
I had this same issue. I took the car to a ford dealer to have the battery replaced under warranty. They informed me that it was not the factory installed battery. That was impossible since I bought my bullitt brand new! After arguing with the service manager I just bought a new motorcraft. Now three years later it is doing the same thing. CD player radio is trying to cycle the CDs. I noticed it starting this fall as it got cold it was making a strange noise while I was trying to start it. Now in March I went away for a few days car parked in the garage, got home tried to start it and it was dead. Hooked it up to charger it starts and ran a few days. We got snow so she sat for the weekend in the garage and again the battery is dead. Hooked the battery up to battery tester it shows the battery as good... Very frustrated! you cannot tell me that ford doesn't know what causes this and has a fix for less than a down payment on a new challenger!
3/3/15, 07:54 PM
#19
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Yes, actually, I can tell you that Ford doesn't know what causes this. As to the price.. well... no, I can't say anything about that.
Seems to be a "chicken or egg?" issue, near as I can tell, and the problem is neither one knows which is first.
If the terminals get corrosion, that'll cause the alternator to go out due to overwork.
If the alternator is going out, say, bad diode, that'll cause the battery to go whack, and then THAT will cause the alternator to go out too.
If the battery for whatever reason is just a weak sauce POS, that'll cause the alternator to go out.
If the alternator is constantly charging the battery, the diode pack goes out, and then the alternator is shot... AND the battery is going to die right after.
It's just... frustrating.
That being said, I guess I'm different than others on this. I don't *even* care if the alternator goes out. I go get it tested, they say 'yep', they plop a new one on the counter, I go swap it and while I'm at it clean the throttle body and reset the computer, take the old one back, and off I go for a while. I have a lifetime O'Reilly warranty on that item. So far, they just keep swappin' them.
I should do the multimeter fuse thing though. Just to see what happens.
Oh, and momstang? Welcome aboard!
Seems to be a "chicken or egg?" issue, near as I can tell, and the problem is neither one knows which is first.
If the terminals get corrosion, that'll cause the alternator to go out due to overwork.
If the alternator is going out, say, bad diode, that'll cause the battery to go whack, and then THAT will cause the alternator to go out too.
If the battery for whatever reason is just a weak sauce POS, that'll cause the alternator to go out.
If the alternator is constantly charging the battery, the diode pack goes out, and then the alternator is shot... AND the battery is going to die right after.
It's just... frustrating.
That being said, I guess I'm different than others on this. I don't *even* care if the alternator goes out. I go get it tested, they say 'yep', they plop a new one on the counter, I go swap it and while I'm at it clean the throttle body and reset the computer, take the old one back, and off I go for a while. I have a lifetime O'Reilly warranty on that item. So far, they just keep swappin' them.
I should do the multimeter fuse thing though. Just to see what happens.
Oh, and momstang? Welcome aboard!
3/3/15, 08:18 PM
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It is so sporadic. My 08 Bullitt factory battery is still going strong. I store it in my garage from Nov to May every year, the CD's are emptied, everything is turned off including the fan (allowing the blend doors to close) before shutting the engine down. I do not lock/arm the alarm, and the battery lasts up to 8 weeks before needing a charge. So I run it up to temp every 4-6 weeks.
Last edited by cdynaco; 3/3/15 at 08:24 PM.
