my77stang

did anyone ever pinpoint the problem with our batteries dying after sitting for a day or two? it happened to me a couple times while the car was under warranty but ford never could do anything. now that its out of warranty its been doing it almost every time we let the car sit for more than a day.

Nuke

Have you had the battery load tested to rule out that it's not the culprit first? If you KNOW the battery itself is good, then you have a drain somewhere. Begin troubleshooting to determine the source of the drain.

Place an ammeter at the battery and note what your leakage current is. There WILL be some since the antitheft system and radio have some minimal draw. I don't know what the normal value is but my guess is well below 250 milliamps. One-by-one, start pulling fuses noting what circuit each one is. The intent is to find the circuit that is causing the drain, then go from there. It can be a real pain in the *** but well worth the effort.

The only issues that have been brought up on the forum (did you do a search?) that I can think of offhand are faulty Motorcraft batteries pand battery drain due to the Shaker systems.

crazyassracer

They do?

conor1148

i heard that in some cases it was caused by your shaker 500 changing cds while its sitting still and turned off. not sure about that though

mcburns36

I read the same thing about the Shaker system.

Nuke

The Shaker system issue has to do with the amplifier continuing to draw power with the Shaker system NOT turned off when the ignition is off.

Analyzer52

You know I'm not one to care which way someones political views are but your signature is ridiculous and I'm surprised the admins have allowed this. It's one thing to be for a candidate is another try to spread clear obvious B.S. with this terrorist crap. Your signature is borderline racist.

And for the record I'm a republican and still offend by your signature.

Carry on with the thread.

svfetter

Certainly any Mustang could have a bad battery or an electrical problem but as it has been stated many times on this forum as well as other Mustang sites, there is nothing wrong with these cars generally speaking regarding this issue.

This problem comes from the computers in these cars running too many programs or systems in the background when the car is sitting idle draining the battery. Active alarm system can be an issue and it has been shown that leaving the radio / CD on when turning the car off leaves the amps on when the car is off magnifing the issue. My Expedition will do the same thing under the right conditions. Nature of the beast in cars these days.

If your car sits for more than a couple days it needs a battery tender. Although It has been shown that some cars are more sensitive than others on this issue.

Doogie65

Great information. When mine was dead this summer after sitting for a couple weeks, thought it was a fluke as I double checked everything and the only thing that was in the "on" position was the stereo... even though the ignition was off. Sounds like I should just throw a battery tender on it and just have to live with it.

StangHarley

Mine goes dead after 3 or 4 days. Since I bought it used, I figured it was a weak battery. Guess I'll put a battery tender on it. Does anyone know of issues with a battery tender while an exterior car cover is on?
OP - I like your sig. Maybe you should add something about The Antichrist.