New CMU required for wireless Carplay upgrade?
 

I have a 2017 Mazda 6 that I’d like to upgrade with Apple Carplay. I found the USB hub retrofit kit on Amazon for $95, but I then saw that I could get a unit that supports wireless Carplay for $140. I went for the wireless option. Now, I’m reading another forum post regarding the procedure, and I saw someone claim that I would need to upgrade the CMU in addition to the firmware and USB hub. This would make the wireless upgrade much more challenging and costly. Can anyone verify whether a new (2021) CMU is needed to support wireless Carplay?

No it's not necessary to replace CMU, what you have seen on Ebay or Amazon it's a Chinese knock-off USB hub integrated with a wireless Carplay module, Mazda never made this type of wireless HUB. Just follow installation instructions and before you replace hub upgrade CMU to any version larger than 70.00.021.

echermak Welcome to the forum