99GTvert

Is that a security feature? Just seems like a pain in the *** if the battery goes out one day unexpectedly.

08'MustangDude

Not supposed to happen.... I replaced the battery in my Mustang, no issues with anything.

JimC

That doesn't make any sense. How does the loss of battery power affect a MECHANICAL lock? More than likely your lock is gummed up and so the key won't work. I had that problem on my 2006 when I accidentally locked the keys in the trunk (and in a convertible you can't drop the back seat to gain access). The locksmith said that using graphite on the lock to keep it working actually caused the problem that wouldn't let me key work.

08'MustangDude

I have two sided keys, and you're supposed to be able use them in either orientation,
but they'll only turn the cylinders inserted one way. The FORD logo has to face the
windshield with the ignition, but face rear of the car for the door lock... Ford scrapped
two keys before getting it right, they said someone messed with the lock cylinders.

With the battery disconnected, you should still be able to open the driver door with the key,
just no the FOB, of course... Being a coupe, you can wedge the window open, and use
a hanger or something else to open the door from the inside, to tap the unlock button.
That, or a slim-jim, call "AAA" or a local police officer, they can open it with a slim-jim.

Or like this: