iPhone 6s doesn't turn on

After screen replacement phone doesn’t turn on and no response with itunes.

I only have a multimeter and I checked below.

Checked battery and got 3.45V

Checked PP_BATT_VCC and got ~120K ohm and keep increasing..

PP_VCC_MAIN: ~70K ohm

PP5V0_USB: ~1M ohm

Checked voltage PP_BATT_VCC, PP_VCC_MAIN with USB charging cable connected : 30-60mV.

Any clue?

I replaced my broken screen and I messed up with installing front camera cable assembly. I accidentally connected front camera cable to display connector and I felt something near the connector was getting hot.

I realized I did everything wrong and I started over and reassembled but the phone won’t turn on.

Any comment or help will be much appreciated.