On my 2018 there is an OBD2 port tucked up under the dash behind/below the gauge cluster.  I can plug my cheap bluetooth OBD2 adapter into it and get realtime info like RPM, coolant temp, etc.  Can I read fault codes with it?  Reason I ask is because I was on a trip this weekend and my CEL came on and flashed continuously for a while.  No pattern, just constant blinking.  We stopped for a break and once I started it up to leave a while later it blinked for a short time then went out.  During the rest of the ride home it occasionally came back briefly.  Seems like a loose connection somewhere maybe because I'd hit certain bumps and it would flicker, or maybe water somewhere.  Anyways, I plugged the scanner in today and it showed no faults.  Does this system not log old faults, or is it a different protocol that my scanner can't read?  I'm using Torque Pro. 

Also, I thought about just leaving the adapter plugged in all the time, I planned to waterproof it and secure it up inside the dash but it is getting power at all times even when the key is off.  Is there a way to change this so it's only powered when the key is on?  There are two bullet connectors coming from the plug and its wire bundle, male and female, both orange.  Looks like they would connect together but I didn't want to try it and fack something up.  I'd just like a way to easily check fault codes if they come back without having to take the dash apart to access the port.  If I can't leave the bluetooth adapter connected, I'll probably pick up an OBD extension and mount it somewhere I can get to easily but I thought it would be handy to just have it permanently plugged in.  It's not crucial or anything, just one of those things to make stuff a bit easier.

Edit to add a pic of the obd port and extra wires https://i.imgur.com/CDnFoFa.jpg

With my '17 had that. I had to build my own :-(

You should be able to record the data over time and then play back the data to see what's up when the light is flashing.