My PSP won't charge

is there any ideas as to what might be the problem with my PSP. I had my PSP put up for awhile and when I got it back out I couldn't get it to charge, the battery had gone bad while it was put up it had swelled up so I bought a new battery online and a new charger because I can't find the original one. when I got the new battery it came back to life and worked fine but when I plugged in the charger it still wouldn't charge so I used Tue USB charger with my ps3 and it started charging so I left it alone awhile but when I came back to check it it was dead, wouldn't turn on or anything. I have no idea why it did that. When I plug in the wall charger the orange light does not come on even when I wiggle it because it is one that does not fit very well so I bought a new yellow charge port cable and replaced it thinking that could be the problem and bought another new charger, one the fits correctly and still nothing. I was able to borrow a battery from another PSP to check and see of mine would even turn on then and it did just fine so I know that it is something with the else. Like I said I replaced the yellow charge port cable already but I am wondering what else it could be. I have read something about a fuse and a few different things but I was hoping maybe someone would have a better idea what it could be before I started trying to replace everything or have to find somewhere to repair it. If anyone can help I would greatly appreciate it this is really irritating and I just want to get it fixed. any thoughts and ideas are welcome thanks.