Old Iphone 3G not charging?

You probably missed something putting the phone back together again after changing the screen. Sorry, but in this case we can't help you, Apple does not allow users or any other 3rd partyto open the phone, without voiding the warranty. This also excludes your device from getting service from Apple.

So you'll have to find a 3rd party repair shop and hope that they can find out what went wrong.

wull123 wrote:

I recently found my old Iphone 3G, I was going to use it for music. The screen was cracked so I have replaced the screen but when plugged in it shows no life or indication of charging? Any Suggestions?

If it went for a long time without charging (months), the battery is probably dead. Lithium batteries must have some charge on them all the time or they will fail. Apple devices take this into account; "0%" is not really completely discharged; they shut down with some charge remaining, enough to keep the battery alive for several weeks. As you've opened it already to replace the screen you might try replacing the battery. This is unofficial advice, of course.

But also remember that your phone is 5 generations out of date; maybe it's time to get a new one. There are very few apps that will still run on an iPhone 3G.