Hazard lights flashing

[Nex]

Maybe someone cut the horn wires and tried braking into your truck.

 

[NHbeast]

The best answer I've seen is that weak/old batteries can make late model F150s do strange things.
The original battery was almost 5 years old.
We recently had a cold snap, -15 F.
Truck started noticeably slower the next day after sitting a couple days.
Bat voltage was 11.74 after resting.
Had the bat tested...failed...time to replace.
Got a new OEM bat.
Service guy had no explanation for the flashing.
He wanted to test for a parasitic draw...
I wonder how much that would cost to check?
5 years is good life for a battery.
No thank you.