The dealer worked on ours today, but now it's almost 40 outside so I don't know if it's fixed or not.
We will find out, it's going to get cold again this weekend

 

Ford's had this problem for years, as well as other manufacturers. My wife's 2005 Mercury did the same thing last year on the first really cold morning of the winter. Thing is ever since then, the door will not unlock with the key. We have to use the remote key fob. I think it broke the linkage inside the door because we can hear something clanging in there when we close it. I'm too busy to tear the door apart and fool with it, and she's too busy to park the car long enough to let me fool with it! LOL
We sprayed some lock de-icer on it and it's been fine ever since. But on a brand new vehicle, hell yeah I'd take it back to the dealer and report it as a warranty issue.

 

Your 2015 F-150 has a TSB 15-0052. Some 2015 F-150 SuperCab and SuperCrew Cab vehicles built on or before 3/25/2015 may exhibit inoperative door latches during or after freezing temperatures. Either the latch cable will need to be replaced and latch or both.

 

Not happy, it's 7 outside and I have to hold the door shut with my hand to drive it, again the door won't latch, they can't get it in till Thursday.
Really disappointed in my new ford

 

If they just repaired it and you're still having the same problem, I would have taken it straight to the dealer and raised hell. Don't let them put you off like this. Actually I would have it towed because technically it's not even safe to be driven. You're under warranty so they should pay for the towing. Then I would demand a rental or loaner vehicle. If this gets reported enough, Ford may end up issuing a recall for this, once they find a more permanent fix. If the door will not close, or if there's a chance the door could fly open while the vehicle is moving, that is a sufficient safety concern to force a recall.

 

Interesting that this hasn't been fixed yet. I remember around February of 2015 the service adviser at the dealer I go to was telling me the 2015 had this problem and ford was aware of it for a few months at that point. He was telling me never to buy a first year model vehicle as they always have plenty of bugs their first year of production, which I knew.

 

Exactly the same issue as mine. 2015 F-150 with 1600 miles on it, 2 months old. I've had it in twice for the same issue, next time (this Saturday) I'm bringing in a copy of the TSB and show it to them. Then, I'll ask them if they want me to bring my tools in and fix it, too. I can't imagine nobody at the dealer has mentioned the TSB when I keep bringing my vehicle in for this same issue. It took me 30 seconds to find the TSB online. Even if my vehicle was built after 3/15, it's exhibiting the exact same symptoms described in the TSB..

Steve

 

I'm having this issue as well even though my truck was built in August of 2015. I live in Illinois and when it gets cold the doors become unreliable. Electronic locking/unlocking methods have intermittently stopped working for multiple doors. Today, my driver's door would not close after I had to open it from the inside. I was only able to get it to stay shut by pushing down the lock tab before closing it.
I'm no expert, but that seems like a safety issue to me. It's certainly inconvenient and unacceptable for a three month old truck. Thanks to the bull***** date on the TSB, I'm probably going to have to go twelve rounds with the dealer to get it repaired under warranty. Ford should take more serious action on this.

 

Look in the book that's in the glove box, you will find an 800 number, call it, ford will call the dealer and tell them how to fix it. Then ford will call you to follow up on the fix.
For me so far so good, but they had my truck two days