I've receive the "deep sleep mode" message two different times in two years and frankly notice nothing different when I finally do open the door and start it up.... seems completely normal.

 

My truck went into deep sleep mode and the battery was dead. The cabin lights wouldn't even come on. The battery was showing 4.1 volts on my multi-meter. I was installing mud flaps the day before and had started the truck multiple times in a short period to turn the wheels and move the truck in/out of the garage. Don't see how that would cause the battery to drain. I put a charger on to get the battery back up and haven't had a problem since. I'm going to ask the dealer to test the battery when I go in for an oil change.

 

Not true. I leave mine at the airport sometimes for 3-4 weeks and have never seen this message.

 

I wouldn't be to hard on the dealer. Unless they get an experienced tech to look at it all you'll normally get is inexperienced opinions on a diagnosis.

I would bet they will eventually figure it out but it might take a tow to the dealer. I personally would give them a chance to fix it. No way this wouldn't be covered by the dealer. How long had the truck been sitting? If the voltage is below 12.4 volts imight not start.

 

Yes it is true for me as I do not drive it every day as I am Retired and after 14 days the ford app lets me know it is in "deep sleep Manually start to wake up" and I keep a trickle charger on it when not in use and have had no problems. I start it to use it and everything is fine.

 

Sometimes i leave my '16 parked in my pole barn (without starting) for a month or two in the Winter.
In three+ years, never seen this 'Deep Sleep Mode' message with my truck.

IMO people seeing this message often or for short park periods the prime suspects would likely be a parasitic draw maybe from some aftermarket device installed, faulty charging system or a bad battery.

 

My 2015 never did the sleep mode but the 2019 does so maybe it is just the 19's and maybe the 18's

 

I have parked my 2019 Lariat for 18 days, the longest so far, and have never had Deep Sleep initiated. Also I would not use a conventional trickle charger on a AGM battery, I would recommend a "battery maintainer" which is a "smart" device and does not constantly charge a battery after reaching the fully charged voltage.

GD

 

Deep Sleep Mode is a part of Sync Connect. Sync Connect wasn't an option on the F-150 until 2017. Truck owners 2018 and earlier without that option will never see Deep Sleep Mode.

 

FYI my charger is approved for a AGM battery I do know the difference and should have mentioned that.