Chosen Solution
Hola… I replaced my battery and is it possible that one of the 4 plastic board connections is not seated properly..I open the phone and I get a full white screen with the Apple logo , but it then closes and in the background it seems like it is still lit but quite dim…It does not go any further but each time I hit my button it lights up bright like it is ready to rock…..
If you connect your phone to an iTunes enabled computer, is it recognized? If it is, then the first thing to check, as you suspected, is to see if the screen assembly is properly connected and seated. However, I suspect you may have damaged the backlight circuit when you replaced the battery. It’s important to fully disconnect the battery before removing the screen assembly. You also need to re-connect the battery last. Th way the LCD connector is laid out, the voltage pins are next to ground pins so if the connector is powered and you misalign the connector, they can short causing damage to the logic board.