Dropped iPhone 6 in swimming pool. Help Troublshooting Problems

Hello everyone!

So i just recently decided to jump into a pool with my phone (Out of warranty) in my pocket and I let it dry for a couple of days and it won't turn on.

After a few days, knowing its fully dried, i plugged it in for a few hours and the phone became kind of hot. (Maybe an indication that it is charging? Not sure.)

I have a few questions and I would like some help trouble shooting the problem.

1) Will an iPhone 6 turn on without the battery plugged into the the circuit board?

(I tried plugging the charger in without the battery plugged in the I didn't get any response from the phone.

Unless the vibrator and speaker are also out, then i have no way of knowing if it's on or not.)

2) Is there any way I can check if the battery is shorted out or not?

3) Could the USB Dock Charging Connector be out?

Those are the questions I have for now.. any other suggestions would be greatly appreciated!

Thank you