Under the drivers side dash. Can't hear it sitting in the drivers or passengers seat, not under the passenger side dash, not under the hood. Only sticking your head up under the dash on the drivers side, it's a constant hum, 2 pitches, each lasts for about 4-5 seconds before changing. REALLY sounds a lot like a stuck cd in the Shaker 500 head unit. Oh yeah, that's right, I replaced it with a different HU!

Car is off, never ever ever even had a cd or dvd in the new HU. Put my head right up to it, zero noise. Keys aren't in it, I've toggled the heat / ac controls and fan to every setting, I'm completely baffled. Tried to get a video with my iPhone, but you have to turn the volume completely up and can hardly hear anything.

If nobody has any ideas on what this is then I can go try to jam the phone way up under there to see if I can get a better quality sound out of it. Clearly something is churning away and eating at my battery. Maybe this explains why I'm on battery #8 in just over 6 years? Thought it was just the crazy AZ heat.

ANYONE have ANY idea what the heck this could be?

 

If you have removed your key and your door hasn't been opened it's probably white noise from the subs in your door. Mine make an awful noise when the volume is down to zero. Once I open the door or turn the HU off, it stops.

 

Does it sound like a BB spinning around in a plactic cup for a couple of seconds?

If so, it has to do with the gauge cluster. Mine does it too.

 

Key is out, car has been off, doors closed for 2 hours. I came back to the car to look for something and had my head way down under the dash and heard it. Definitely not the subs and definitely not the gauges. Good thought on the gauges though, have had friends that asked me that same question. Just not the sound I'm hearing. Any other thoughts? I can try to grab another vid this weekend as well.

 

Bee hive?

 

I'm pretty sure all the blend door actuators are motorized now, (unhooking battery would be a quick way to confirm its electrical- and it probably is...) but if it still does it with no battery, there might be a vacuum sensor/accessory still somewhere in there...in any event the brake booster has a huge vacuum reservoir also- suggest after shutting off everything pump the brakes a dozen times till all the vacuum is gone from the booster, just to see if it could be some odd vacuum leak...if its the booster you might only hear it near the pushrod hole.

if you pick up a cheep mechanics stethoscope I bet you'll be able to narrow it down further- but I'd suggest taping or shrink tubing the probe except for the very end just to keep from shorting anythin out- also helps isolate sounds from metal tip vs side of probe contact.

if you LEAVE the door open for the full 15 minutes till the lights all go off, does it still do it? if not close/reopen door see if it starts again...doubt a partial short in the lighting circuits would do it, but you never know...sometimes even someting simple as a light bulb can screw stuff up...

 

Try pulling your fuses to see if the sound goes away. If so see what that fuse controls and go from there.

 

Not exactly how I'd describe it but my '09 does make a similar sound just after turning the engine off and I hear it if I sit there for a second or as I'm getting out of the car...

 

Crazy AZ heat makes me believe you use the AC a good deal. My DD Taurus makes a similar noise after I shut the car off, mine happened to be the AC, a mechanic friend said its against the fire wall and it could be your problem as well. Good luck finding the issue.

 

This was all after the car was off for several (possibly 6 or more) hours and had not been driven. The only thing that might be associated is the car sitting for 10-15 minutes until the interior lights and everything shuts off. I will try that next. Car is in the shop getting the trans fluid replaced, so can't test this until I pick it up, which might not be until Wed. morning.

Hey, at least the battery isn't dead yet. 2 weeks and still going strong...

 

Same here with the gauges, its weird. Its like they have to wind down after you turn the car off. I can actually watch mine tick down after I turn the car off. Takes like 5 to 10 seconds. I hope thats not just me

 

I assume you get free battery replacements? Has Ford tried to find the problem?

 

That's not the same problem that the OP is having. But yes, what yall are hearing is the gauge cluster. From what I understand, you're exactly right...they are just winding down. They all do it, and mine's done it for the last 6 years and still works fine.

 

Yeah, I noticed that after re-reading the OP's response. He says he still hears it after leaving the car sit for 2 hours but it's nice to know I'm not the only one hearing my gauges "wind down".