No. The aux input signal to the oem head unit is designed for an "audio" signal only, such as a headphone jack off the phone or other device. It won't accept a signal from a thumb drive or similar storage device because those require an application to read and convert the mp3 file into an audio signal. Unfortunately the 09's did not come equipped with that kind of technology.
It would be easier to have the oem deck be bluetooth capable but on those it is not.
After doing more research and noticing how my mp3 player works in this car, I had come to expect that. Thanks for confirming it before I wasted money on a USB adapter.
I sure like the $69 radio I got at Walmart and put in my 4Runner. It has a USB port on the front. I love being able to plug 8 hours of music into the front of it with a mini (or is it micro?) USB thumb drive. I wish I could do that on this car, instead of screwing around with a cord, and operating my MP3 player (which became illegal to do last year here in Georgia). I have to screw with the player before I get on the road, and not touch it, even at stop lights, to be legal.
That replacement radio linked above looks really nice, but unfortunately is way out of my price range. Thanks for the link, though. Since I don't have that kind of money to spare, I will just have to suck it up and live with what I have. I also don't feel like screwing around with dash face adapter kits to try to make a modern aftermarket radio setup look decent in the dash.
I am really loving driving this car. Talk about a sleeper, in terms of handling. Anyone who hasn't driven one probably has no earthly idea that the car can give a true sports car a run for its money. I drove a Miata for 7 years. This Mazda3 is no Miata, but is sure can still make me grin while pretending I am driving one.