I just want to give a little feedback.
I've had real problems with this system and my SG8+ (and SG7 previously) and tried almost everything I could think of to get things working, the best I got was some crappy Mirrorlink connectivity, (after lots and lots of messing around) but with no real features to even bother with, but now I can get the following to work brilliantly:
Suzuki Vitara 2017 (UK)
Samsung S8+
Android Auto
Plus Mirroring so I can use my Android and all its apps on my car's screen.
What I had to do:
I followed this guide to root my phone:
https://youtu.be/XNznlTJJesc
I followed this guide for the mirroring:
https://youtu.be/bASKUOCAFWM
I followed this guide to upgrade my Suzuki SLDA from 1850 to 1860
https://youtu.be/V9Lu5Xmc3tY
I got the last one from this thread I think, also where I got the update file.
Steps one and two DID NOT WORK until I'd updated my SLDA. I figure this is the most important step.
You may well not need to root if you don't want the mirroring feature (but it's cool and knocks the Mirrorlink offerings into a cocked hat).
Sorry if I haven't credited the right person/comment, I am awash with tabs right now, but just wanted to let people know this combination was all possible now, with very easy guides to follow.
Thanks to everyone who's contributed to this post, it's been a godsend over the months.
(I've also stumbled across a map update for the SatNav, but now I can use Waze properly on my system, I may not need it.)