Found numerous threads reporting that Intelligent Access (IA) stopped working except on Driver's door only. Lots of commentary about replacing the "12 volt battery", implying the car's main lead acid battery. Turns out there is a second "12 volt battery", according to Ford Pass Technical Support - this is the battery causing the issue. More below, hope this helps others.
2019 Edge ST original owner: Intelligent Access (IA) worked on all 4 doors until about 6 months ago - now works only on Driver's door. Called Ford Pass Tech Support, spoke with a technician. She reported that the vehicle has a SECOND 12 volt battery, which is hidden in the dash somewhere and is a backup battery for the cellular modem. This battery is apparently used for IA, and is rechargeable (she didn't know if it was lithium ion or some other chemistry). She remotely read the charge level on this second battery, it was at 36%. Normally this battery is at 85% or higher. If the system measures <75%, the Intelligent Access feature will dumb down to just the driver's door to save battery power. In her training, the battery was also named "12 volt battery", which she found dumb, and confusing to both the techs and customers.
I asked her if the battery is serviceable by customers, she said no due to its (highly) inconvenient location. She also alluded to a potential issue with a connection to that battery, that might be the root cause of the battery not charging properly. I've contacted my local Ford dealer service tech - car goes in next week to check this out. Service tech also made an offhand comment about confirming what the real issue is, regarding connection to that battery. Hmmm. It helped greatly that the Ford Pass tech diagnosed this first; I got the impression the service tech was already familiar with this problem.
