Most error codes can be read at the diagnostics port, Some readers will only show engine codes while the more expensive ones will show all the codes. A special reader is usually needed to display ABS codes. It might be that you would need to use STARR computer which is usually only at a dealership.
I assume you have done the basics and checked the brake fluid level, checked for leaks, and brake pad / rear shoe wear. Sounds like maybe the front brakes are not working or the proportioning valve may be messed up. That is just a guess.
ABS systems can be a bit tricky and could require some knowledge to fix. Might be best to have the dealer take a peek at it. Some dealers will not want you to take the car back if the brakes are not working and might make you sign some sort of release if they don't fix it.
I have a generic code reader, I'll give it a try tonight or tomorrow night and see if I can access the ABS codes. Are there any oddities to getting the codes out of the computer or is it a matter of plugging the scan tool into the port and turning the car to ACC or ON?
Are the ED codes significantly difference (other than drive train differences) from the ICE ones?
I've done brake work before and if it's anything beyond a bad connector or sensor, a pad/shoe replacement, caliper replacement/rebuild, or a fluid leak, I'll take it to the dealer. Swapping out electronics is easy as well as long I'm sure a replacement (usually expensive) will fix the problem.
Failed reluctor rings and failed brake switches appear to be common issues on these cars although I don't think either one of those fits my symptoms. Reports on failed brake switches say that the shifter locks up when the brake switch goes bad although that may be limited to the ICE versions, there's nothing specific to seeing this failure on the EDs. I don't think bad reluctor rings would cause the hydraulic pressure to go away unless the computer shuts down the pump in response but that doesn't make sense to me. My first guess is water in the ABS pump connector or a bad pump.
BTW, it's a 2014 ED Passion. I should still have some time on the 4 year warrantee so maybe I won't have too many out-of-pocket expenses.