It will show an unread message at the top of the display when connected to my phone, but that's it.
I've deleted my phone off the Bluetooth setting on the Ridgeline and unpaired my Ridgeline from my phone ...and have reconnected, still no luck. My phone is set to allow messages.
I'm using Car Play, with the phone plugged into the usb on the dash -- which is the only way it will work. Shows me when a message comes in, and when I select it with a tap, Siri reads it to me. Excellent integration, IMHO
I have apple carplay in my 2015 subaru forester xt, every once in a while the iPhone wont connect and just requires a phone reset. Mine will read and send text messages all hands free without the need to connect the phone to the iphone cable.