"Dead iPhone SE what should I check?"に関する回答Alignment is very important. Not only do you have the battery connections, but the small contacts for the ‘gas gauge’ in the same connector. Align the connector to the main board carefully. Then press down gently but firmly and very slightly rock the battery connector as you press down. When the connector seats it will make a ‘click’ sound. Then press down gently and make sure both sides are seated down and locked in place. If the phone still won’t boot when prompted, there are many, many issues that could be involved that prevent the phone from booting. One of the main reasons is from using non-Apple certified cables and chargers with the phone. These gas station cables and chargers that are not Apple certified can damage the charging IC on the main board. This chip is responsible for making sure the battery isn’t overcharged or overheated during charging. If it is damaged, the phone won’t boot. iPadRehab can give you a quote to repair the phone. You should contact them at their web site and get a quote....
"Dead iPhone SE what should I check?"に関する回答Connect a genuine Apple charger and genuine Apple lightening cable to the phone. It should 'prompt to boot'. If nothing happens, then there are a lot of possibilities. Check the battery connection on the main-board. The battery has a 'gas gauge' circuit. if the phone can't see the gas gauge circuit in the battery, the battery connector may not be seated properly at the main-board and the phone won't boot. The lightening connector in the phone may be damaged. You may need to replace the lightening connector. Try flipping the lightening cable around 180 degrees and plug it back in. The phone should prompt to boot. After that has been checked, and the phone does not boot, then some advanced troubleshooting may need to be done. Check with iPadRehab forums, and maybe get a quote for repair from the main WEB site for iPadRehab. Good luck!