I had the exact same problem last night! My car is exactly the same as well......2018 EX-L about 11 months old. I get 3 brake malfunctions that show up on the dash. Car wont start but will after several attempts over a 10 min span. Once going it ran fine......but when i pulled over to get gas....same issue. Was at the gas station for like 10 minutes trying to get the car going. Going to take it in the dealer tomorrow.
Another thing i noticed.....the rear trunk wont open unless i do it manually. Im guessing its related.
very disquieting that the battery could fail so catastrophically...never had that happen before. my wife had just shut the car off 2-3 minutes previously, so its not like she left the lights on. and she drives a lot...so it's not as if the battery hasn't had ample opportunity to be charged by the alternator.
anyway, was really miffed by the service associate who had no customer service tact in that he at first told my wife that she could be at fault and would have to bill her for $160 until the diagnostics were done. he knew i was pissed and afterward apologized and humbly asked how he should share this "policy" with customers.
i do hope this was the real solution and that there isn't something else going on... the Honda RAssist driver was really poor in dispensing advice. after jump starting my wife's car, he argued with me (over the phone) that everything was fine and she should just drive off as if nothing happened since it jump started immediately which suggested to him that the battery was fine. i vehemently disagreed and sent my wife to the dealer. she had a brain fart and parked in the wrong place. and when she went to restart the car, it again wouldn't start --- same brake warnings and then an added message of not sensing the keyless remote.
finally, how's this for a strange occurrence: just in front of where my wife parked (she was picking up our daughter and a friend from school), a same colored 2018 EX-L AWD had to be jump started too. (yet this guys CRV didn't give any of the brake system warnings...it just wouldn't start)...
again, there must be a slew of bad batteries (i hope), else there is something else worse lurking...
anyway, thanks for everyone's commiseration and advice.