The vehicle I have is a 2015 Mazda CX-5 with about 100k miles on it. It was running fine until the other before the following:
I used the CX-5 to jump my Dodge ram truck which had a dead battery. I didn't drive the CX-5 then for a day or two and when I went to start it, it seemed the battery was dead, I think I needed to drive it around a bit after giving the jump.
I then tried to use my truck to try jump starting the car but it wouldn't work.
Since then I have replaced the battery and had a new starter put in by someone who came out to my house but it does not start.
There is a code: U0101 which seems to have something to do with not being able to communicate with the TCM.
The vehicle powers on fine as far as the dash, etc. I took the videos below to show what happens when I try to start it:
video 1: When I get into the vehicle and touch the brake with the key fob inside the vehicle, the key light is solid green, which I think means it is successfully detecting the key fob: https://www.youtube.com/watch?v=E1X96vWV9gM
video 2: This is a video of the dash when I am pushing the keyless start button with the key fob inside the vehicle: https://www.youtube.com/watch?v=QvKDft2MYbQ
video 3: There is some kind of noise that happens during the same time as video #2, I put my camera under the vehicle to record it: https://www.youtube.com/watch?v=nJdzJOjYqsk&feature=youtu.be