The manual states that the largest size for the flash drive is 32gb formatted with FAT32. I know that others have used larger sized drives but I believe that they created partitions on the larger sized drives. I've been using 32gb and FAT32 with no problems.

 

For the 2021, with the revised Type B infotainment (10.25 inch screen), it is really hard to find anything on the USB flash drive limitations.
The manual talks about the two ports and calls it

USB1 Video/USB2 Video

Maybe someone smarter than me can tell me what that means.
Apparently only the top port with the USB symbol is meant for AA or CP connection, however.

 

I know that one of those USB ports has a higher current output than the other for charging cell phones. That's about all I know since my MX and CX don't have carplay.

 

I bought a 2021 CX5 Grand Touring 3 days ago. Before buying I did a lot of research and found the online CX5 Online Manual to be very helpful. I really wanted an aux jack to connect an MP3 player to. The manual clearly showed the 2 USB ports and an aux jack along with the SD card for a GPS. When I asked the sales person if the car had an aux jack he assured me it did. When I got the car home and started going over the features I realized that there was NO aux jack. I went back to verify online.
This AM I called Mazda "Consumer Experience" to see what was going on. After a half hour wait I finally got an agent. I explained my issue. She put me on hold for another 10 minutes to research the question. When she came back she told me there was no aux jack and the salesman was wrong. I pointed out the manual I had looked at online. I even offered to send her the link so she could see it for herself. She then asked to look into it further. After another 15 minutes she hung up.
You would think that after spending $30K they could do better. During the long wait periods they had the nerve to play a recording saying how important customers are and how Mazda is dedicated to........
I was determined to figure it out. Did I have a trim level that did not include the jack? No. Was the owner's manual in the glove box wrong? Yes. Was the online manual wrong? Yes.
So this time I went back online and specified a 2021 CX5. This time the manual would not even tell you where the USB ports were located when searched for. I finally waded through the manual page by page and found it. THE 2021 MAZDA CX5 DOES NOT HAVE AN AUXILLARY PORT ANYWHERE.
Thank you Mazda sales person and Mazda Customer Experience agent FOR NOTHING>

 

I recently bought a 2021 CX 5 Touring and was looking for the Aux jack too...I then thought it must be in the Grand Touring but apparently that is not the case either. I presume then that there might be one in the Signature trim. I did find a USB Male to a 3.5mm male jack that will do the trick though. You can find them cheap at the usual webstores. Just make certain you buy the audio cable version, not the charging/data one.

 

No, the aux jack was dropped for 2021 but Mazda did a terrible job of not explaining that. Does your device support Bluetooth, I wonder if that would be an option?

 

I ended up buying a Bluetooth CD player from Amazon. I often have issues getting it to connect with the car, but when it does, it works okay. I only wanted it to sometimes listen to audiobooks that I borrow from the library, so burning CDs to a USB drive was not really the way I wanted to go.

 

Thanks for this info. I may give it a try.

 

Max,
If I may ask for more advice, do you think either of these would work for me?



Thanks,
Laurel

 

I don't think the CX-5 will support USB to audio adapters. They are mainly used on computers or cell phones.

I was a little disappointed too my 2021.5 CX 5 did not have the Aux jack as well. They took it away with the new 10.25 infotainment system. Luckily my MP3 player has built in Bluetooth so I just use that.