Dead!!

Dead

I've seen that happen to a couple people on various boards. Did you have active anti theft on ?

Same thing happened to me! Except, after i got my car running again, i noticed the courtesy lights were on, the car was recently at a dealer and they must of bumped the dial. It was sitting for two weeks until i tried to start it. Oh, it also turned off the short drop window feature (only on the drivers side). Make sure both sides are working, or you'll find out after it rains!

Had that problem off and on for two years on my 99, dealer never could figure it out. I ended up dateking to a friend who was very good with electrical stuff and he traced it to the radio draining the battery somehow, took it back to the dealer they replaced it and it has been good ever since. May not be the same here but just a thought.

You could still have a cell dead or very weak cell in the battery. It may show you have a good battery during test but sometimes it does not (been there!). You may also have a loose cable somewhere or your battery terminal cables were not tight or making good contact. Also, if you do a lot of short drives...this will not fully charge your battery and over time your battery will be below full charge. Each time you start the car, a little charge is removed and must be replaced by driving for a sufficient time (20-30 minutes minimum) to give back what was used to crank the car. Also, if you play the radio, run the heat/air, lights on, etc...these will pull power from the charging process. These are normally powered by the Alternator when the car is running, but pull the battery down when sitting parked (engine off) and using them. Also, if you do a lot of sitting in slow or congested type traffic, you are not charging the battery fully either. All these things draw down the battery or prevent it from being re-charged fully.

The new Mustang has a lot of new monitoring systems and may be one of those that if there is not sufficient charge in the battery, it will shut down everything to a safe mode. I would be curious if we have that on the car.

If your car is not a daily driver, I would suggest a Battery Tender type trickle charger for the car. It is safe to leave it plugged in all the time. I use them on my Motorcycle and my last garage queen ('91 RX7 Conv.). Keeps the battery fully charged all the time.

However, even with a fully charged battery, the anti-theft and any other slow trickle losses (radio memory, computer memories, clock memory, etc.) should not draw down the battery even for just 10 days. Maybe a month or so might. Keep us posted if you find the real cause or not.

What radio do you have? Some of the Shakers have been known to continuously "seek" CDs, even when the car is off & parked, for hours on end & draining the battery. Could be any number of electrical things not completely "off" when they should be...

drained battery

Mike Wyatt said:

Went out this AM, and the 05 GT was dead- not a bit of charge. The trunk wouldn't open, no courtesy lights, nothing on the dash, no radio- nothing. It was 45 degrees, so not too cold.

I got it started, took it to the dealer- all checked out OK- charging 13.8 volts, battery good, etc. It had been in my garage for about 10 days, and no lights or anything were left on. The dealer says that I should always start it weekly, but I have a hard time believing it would discharge 100% in 10 days??? Hmmmmm......

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I've had the very same problem with my 05 GT. after being in my garage for 3 different 10 day periods. my battery was completely drained.. so far, I've already gone through 2 batteries and am currently on my third one, since purchasing my 05 on 2/13/05 took the car back to my dealer, and all they did was replace the battery, their service dept. could not determine nor diagnose the cause, or should I say, thats what they claimed.. so after taking the car back the second time, the dealer recommended that either I use a trickle charger, or have them install a battery shut off switch, if the car is not to be used for more than a week, which I feel is absolutely ridiculous...especially for being a 25k+ new car. if anybody has any suggestions, ideas, recommendations who has also experienced similar problems..I'd be extremely greatful for any advice and input...I've also heard that the problem may be the shaker 500 that could be draining the battery..could that also be a possibility ??

GOLDENPONY said:

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Why would he lie?

Johnnygreen said:

Why would he lie?

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He was calling BS on FoMoCo's answer I beleive.

I have the same problem. If my car doesn't get started for 2-3 days, it will be completely dead. I spent about 6 hours diagnosing it one day, pulled half the car apart practically. I still have more to check out. I have to keep a jumper pack in the car. Really annoying.

Same here after a two week no-drive period. Strange side effect, I had to hit the fuel reset switch before she would crank.

dwcinga said:

What radio do you have? Some of the Shakers have been known to continuously "seek" CDs, even when the car is off & parked, for hours on end & draining the battery. Could be any number of electrical things not completely "off" when they should be...

Click to expand...

I've had the very same problem with my 05 GT. after being in my garage for 3 different 10 day periods. my battery was completely drained.. so far, I've already gone through 2 batteries and am currently on my third one, since purchasing my 05 on 2/13/05 took the car back to my dealer, and all they did was replace the battery, their service dept. could not determine nor diagnose the cause, or should I say, thats what they claimed.. so after taking the car back the second time, the dealer recommended that either I use a trickle charger, or have them install a battery shut off switch, if the car is not to be used for more than a week, which I feel is absolutely ridiculous...especially for being a 25k+ new car. if anybody has any suggestions, ideas, recommendations who has also experienced similar problems..I'd be extremely greatful for any advice and input...would it also be possible that the shaker 500 may be the cause of my batteries to drain ??? I've heard that most shaker 500's that were installed prior to April were defective and that Ford was well aware of this issue and has since takes steps to correct any bugs that were causing battery problems...if anyone has any info. about this.. please let me know...thanks much 05 torch red mustang gt.. pittsburgh, Pa.