For 2014 & 2015 Jeep Grand Cherokees, when upgrading to a RA3 or RA4 from a RA2 the customer will lose their ability to use a SD card slot on the USB hub.
The only way to retain this feature is to get the customer a 2014 or 2015 part number or flash the RA3/RA4 to a 2014 or 2015 firmware.
Then the SD card slot will work and show up on the radio upgrade.
This also applies to replacements and repairs. 2014 & 2015 will need same part number replacements or need the radio flashed to the correct years.
If we repair the radio with a motherboard from a 2014 or 2015 then they will retain feature. If we repair with a motherboard from 2016+ then they will lose the SD card feature.