2005 Mustang GT Dead Battery

[miamimike]

Thanks Art for the constructive response much appreciated.Both the battery and alterator check out ok.Battery terms reading shows a drain from 12.5 to 12.25 over a 24hr period.I will do as youve advised,and see what transpires.

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[Art161]

Originally Posted by miamimike

Thanks Art for the constructive response much appreciated.Both the battery and alterator check out ok.Battery terms reading shows a drain from 12.5 to 12.25 over a 24hr period.I will do as youve advised,and see what transpires.

That's way too much of a voltage drop. But also consider this. A battery showing 12.5 volts is only about 80% charged. If you give it a good charge, it should be reading around 12.65 volts. Before you determine the true battery voltage, you need to get rid of the surface charge. Don't go out on the highway for a couple of hours or use a charger, take a reading, and settle for 12.65 volts. It should be much higher. Turn on the headlights for a couple of minutes and then let the battery "recover" for a few minutes to get a more realistic voltage. Or let the car just sit for a few hours after it is charged.

I never saw a reading on my original battery over 12.6 volts after removing the surface charge, which is a touch on the low side. It was down to about a 60% charge after sitting for a week. When the battery died after a little over 2 years, I got a warranty replacement. The replacement battery generally reads 12.76 volts (wow!) after removing the surface charge and reads over 12.6 volts after sitting for a week.

My parasitic draw was measured as 40 milliamperes, and the alternator output was okay.

BTW, the Ford dealer said my battery was okay when I brought it in. The service advisor used a hand held testing device. I insisted that the battery was bad. I had used a hydrometer to test the cells, and five of them were bad, with the sixth being reasonably good. The service advisor was getting a reading of 12.64 volts and told me the battery was okay. This was without removing the surface charge. I turned the headlights on for two minutes. Then he got a reading of 12.18 volts. The car was taken to the "real" area of the shop. The end result was that they replaced the battery.

I don't think you mentioned what type battery you have. If you did, I missed it. If it has caps that you can remove, I recommend that you use a hydrometer to test each cell. That can uncover a problem that just testing the voltage will not. It will tell you whether the voltage drop is because of all the cells getting too low in specific gravity, or whether there is a specific bad cell or a few cells that are bad.

Keep at it. It CAN be fixed.

[miamimike]

Thanks again Art.Certainly plenty of food for thought.The replacement battery is sealed and manafactured by Varta (not sure if you have them over there).Obviously theres lots of forums in both the US and here.Theres lots of theories about shakers etc,but as stated this car doesnt have that issue.Amazingly,no-one on any forum has a definative explanation as to the precise culprit of the draw.There must be a common denominator surely,given the number of "victims".In the meantime "the baby" sleeps,or does it!!?.

[tongy89]

I have been in a battle with ford with this battery issue for about 3 years now.

They wont do anything about it. they cant fix something that isnt broken blah blah blah

tired of them already

[superjoker]

Originally Posted by tongy89

I have been in a battle with ford with this battery issue for about 3 years now.

They wont do anything about it. they cant fix something that isn't broken blah blah blah

tired of them already

I was told It's a power relay, It's a shame really, I sold the Legend Lime 2006 Mustang GT(It was as loaded as I could find and I'd looked for months too) back in 2007 as Ford wouldn't do anything except to jump start the car or haul the car into the local dealer to be charged up(I should have bought the 2007 or a used 2001-2004 from Carmax or somewhere), Just cause I had parked the car out under a car port in the winter(I have no Garage) and only ran It twice a week to go get the mail(Mail isn't delivered out here to the street address here), This was mentioned to Me in this thread(two posts):
http://www.hardforum.com/showthread....post1034585471
http://www.hardforum.com/showthread....post1034585697
Of course I found out Ford fixed the problem in 2007, But when I asked Ford Dealer what the fix was, They didn't tell Me squat. And I spent about $34,000.00 of My inheritance(The rest of the $80,000.00 went on clothes, a house, etc) on buying that car too. Now I couldn't finance a 2001 Mustang GT, Even If I wanted to and I do too(I just don't know of a place that will loan to guy who gets SSI[Supplemental Security Income] with a tax free income of $850 a month(I'm disabled physically and mentally). Could I do payments and insurance? Sure, Just no credit and no legal ability to save more than $2000.00 total. Water under the bridge says the dealer where I'd bought the car new, Perhaps their right, Time to move on and use the knowledge to My advantage.

I had the Shaker 1000 and LoJack, And It was a premium car too.

[Petglibgt]

Got my car back after a second trial to fix the dead battery issue...and yes it is fixed !
They said it was an issue between the main fuse box and the battery ? In any case...haven't driven the car for a week now and started perfect on Saturday. Before the - it was driving me nuts. So for all the people out there with battery issues... yes it can be fixed but took the dealership two times +/- 5 days to fix.