Iphone 5 can’t boot and heat

Hi Forum,

Here I have an iphone 5 which is fallen down to the ground. I changed screen and replaced the battery. Phone doesn’t start…
I noticed the main board heat near U7 when trying to start, particularly L15. I have tested with a frozen spray.

Do you think I just need to replace L15? Or should I replace U7 too ?
You may think about an other problem ?

Thank for your help