My iphone turned off and won't turn back on? How to fix it?

My iphone 3gs had around 95% battery and it just shut down while I was using it. My power button broke a few months ago which wasn't that big a deal because I could just turn the phone on by charging it.

However, now it shut down and when I plug it in it only shows the apple logo then shuts down again.

I don't think the problem is the cable cause I've tried three different cables of my own and one that belongs to my friend and they all had the same end result.

What could be the problem here and how can I fix it?

I live in Brazil and here it's pretty expensive to take to an apple store or something. I don't have the money for that, so if there's something I could do myself then please enlighten me.

I would consider restoring the device back to factory settings, if the issue still shows afterwards, it may be a hardware problem. Stating that you currently own the "3GS" that is discontinued and very very old, it may be that the recharge cycle of the device has run out. Your battery is now malfunctioning and needs to have it's battery replaced in order to have it working again.

If this was the iPhone 4 and up, you simply would unscrew the two screws on the bottom and pop in a new battery ($5 on eBay). Since this is the 3GS, I would consider watching a YouTube video on how to install the battery. It will take alot of effort since the device is quit old.

Best of Luck Jay Jay the Jet Plane!

Try rebooting it by pressing the top shut down button and the home button at the same time. Keep pressing until you See an apple logo pop up in the screen