I have a iPad 3 16gb wifi only. If I turn it on, it will only show the apple logo and then the iTunes logo. Plugging it in to the 10 watt charger will cause it to display the red battery charging symbol (indicating the battery needs to be charged). It does not seem to charge. I have replaced the charging port, but nothing changed. Does this mean I have a defective battery? Is it possible that there is a problem with the logic board?