App,key fob and keypad are doing NOTHING if the 12v battery is DEAD !! So your fob isn`t really any smaller than the OE fob.That hasn't really been a concern for me because I can unlock the vehicle from my phone and even if the battery is dead, it can simply be placed into the center console and it will start up. Other drivers have optioned their Bronco with the keypad which will get them in the same way
Either that or I can include the blank and you will need to get it cut then add it to your keyring. Batteries do go bad, so that is a valid concern. I use the Ford app, as I am sure you may use as well, and it alerts you if remote features have been disabled to preserve battery. Most of the time this alert is a one-off if it's been sitting while on vacation or you've been eating up the battery camping in the car, etc... This usually goes away once the vehicle is started up and the alternator has a chance to do it's job. The other alert that is more of what you are talking about is usually about the health of the 12V battery. The system is actively monitoring the status of your battery, but I also keep my screen on the gauges usually to monitor boost and the battery level myself. Usually if the battery has enough juice to let you into the car, the real problem would be not enough juice to get it started. I write all of that to say it's not a concern of mine as the app has been pretty on point in alerting me beforehand.
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