Why won't my phone charge?

First, check that the charging chord is not damaged in any way. If the chord is unbroken, check the contacts at the end of the chord for burn marks. If there are burn marks on the contacts, then the charger has short circuited and will need to be replaced. If the contacts are in good shape, then check the phones charger port. Make sure it is clear of any debris. If you see debris in the port, such as lint, use a needle-like object to remove the debris from the port. If none of the above apply and your phone does not charge, then the battery is faulty and the phone will need to be replaced as the battery is embedded into the motherboard.