I've got a 2014 V6 Coupe. Bought it in Sept. Everything was great, love the car. Parked it for five days, went to start it, the battery was stone cold dead. Pulled the battery, measured 4.5 volts. Charged it over night, battery will start the car, but the little window sensor shows red rather than green. The last time I drove it was during the day, so the lights weren't left on. The light switch was in the off position. I'm sure the doors were closed and none of the overhead interior lights were left on.

Has anybody experienced this with the newer Mustangs? Googling this topic shows this problem seemed to pop up in the mid-2000's Mustangs.

I have an appointment with the dealership on Friday. I want as much ammunition going in as possible.

Thanks for any input.

 

No issue here, but on a different car I had an early hour failure just like that once when it was REALLY cold (below 0 deg. F) and had left the car out overnight. Probably just a bummer of a battery.

 

Ford battery's are not that good to start off with so leaving it in the cold for a few days without starting it most likely killed the battery. I had something like that happen to me. You can either buy a new, better, battery; go to Ford and get a new one or have your OEM checked, and just keep a battery booster for those times when you know your going to go a few days without the car starting.

Matthew

 

It sounds like you have a defective battery. Mark the existing one someplace so you can tell if they replace it.

I have a 2013 with 12K miles on it.
I bought it 14 months ago, and when I took it for the first test drive on the dealers lot, the battery was dead. The dealer wheeled out a battery charger, and we were on our way in a few minutes. I took it for a 20 minute test drive, and stopped the car. The salesman wanted me to park it in a different place, but it would not start again. Something was wrong, the test drive should have given it sufficient charge to start again.

They took it back into the service dept and quickly fixed it, he didn't say what he did,
and I ended up buying the car.
I've never had any further problems for the last 14 months.
And I have left it for a few days a few times, I leave the headlights in the automatic position all the time. And I've left a phone in it charging overnight several times (The 12V outlets stay on even when the car is off), with no problems, no sign of a low battery. Though I do carry jumper cables in the trunk.

When you get the car back, plug stuff into the 12v ports, phones or whatever you have, leave it there overnight, and make sure it's all ok. And carry jumper cables.

 

Thanks everyone for the input.

Dealer checked out the battery, says nothing is wrong. Refused to change the battery under warranty. I figured that would be response. At least I've got the problem documented if it's a reoccurring problem.

 

Did the Dealer check the current draw from the battery when the car is off? Should be about 150 mA for 15 minutes then drop to 10 mA to 50 mA.

 

Thanks,

I actually checked this before I brought it in. There's definitely a two step drop in the current draw once it's shut down. The way the battery died so quickly, I thought I was going to see a couple amps of continuous draw. No dice - just a low parasitic draw.

 

Motorcraft batteries aren't all that great to begin with. I bought a new one after noticing my green LED indicator was no longer illuminated. Why wait to get stranded before replacing?

After seeing these videos I decided on an Odyssey. Worth the price if you're going to be in your car for the long haul.

 

I haven't had any issues with my Mustang- nearly 20 months now and it sits all winter. Last winter it sat from Nov 26th until mid May outside in the cold never started. I did charge it twice over the winter for about 2 hours each time.
This winter it has been unusually cold, or perhaps just a normal MN winter with several days of sub -15* and again car sits outside and battery is in it and hasn't been driven in over a month. I did just go out this morning and hook up the charger-the battery was down to 12.2v.

On another note, we just bought a brand new 2014 Focus SE, it was manufactured in Mid October 2013 and sat on the dealers lot with its 2.4 miles on it until we bought it a week ago, battery was dead and frozen and had to be replaced with a new one. They did jump it to get it started fro our test ride, but it would not restart again after about 30 minutes of driving and letting it idle at the gas station to fill it up. They just installed a new one right away while we finished up paperwork. I also had a 2002 F350 diesel, the oe original batteries in that lasted 9 years, so I have actually had good experience with oe batteries in all my ford vehicles with all of them (sans Focus) lasting atleast 8 years.

 

Unfortunately most batteries aren't made in the USA anymore and are not the same as those from 2002.