How to fix Samsung Galaxy SII bootloop (Samsung Galaxy SII SGH-T989 T-Mobile)?

[Alzzi]

My Galaxy S2 has recently been stuck in a bootloop for a couple of days now. Whenever I try to turn on my phone, it initially flashes the samsung logo, and then goes onto the screen on which it says "Samsung Galaxy SII Android 4G T-Mobile" with the blue loading bar underneath. The loading bar loads almost the entire way and then freezes, until the phone vibrates and restarts the whole process again.

Occasionally, after the loading bar is frozen for a little bit, it will show the samsung logo again and just get stuck there until it is turned off again.

I can't quite figure out what I did to trigger the bootloop, since the phone is on the stock ROM. It's not rooted and doesn't have any sort of custom ROM whatsoever.

Anyway, I've been exploring google for a couple days now to try to find a solution to get my phone working until I get a new one in a month or so.

I've tried several things now with no avail:
- I took the battery out and replaced it several times
- I've left the battery out for several hours before replacing it
- I've attempted to enter recovery mode, still boots up the same way I mentioned above
- I've attempted to enter download mode, boot up the same way as before
- When I plug the phone into my computer, the phone charges but my computer cannot recognize it
- Samsung Kies also can't recognize it
- I've even disassembled the phone to clean it
using isopropyl alcohol
-Also, usb debugging mode is not enabled

The main problem for me is that every solution or fix I've found requires the phone to be able to enter recovery mode or download mode, and I cannot find a way to get my phone into either of these. The best bet I've had so far is using an update.zip method with the SD card, but every single one of these I found seems to require that the phone goes into recovery mode.

I'm not too familiar this type of stuff yet, so any help would be greatly appreciated! Thanks in advance everybody!

EDIT: After some experimenting, I discovered that when I hold both volume buttons and power on the phone, I come to an error message screen with the android robot laying down and a red triangle with an exclamation point with a message that reads "--Verifying internal MMC Block... checksum confirmation -> check(0) Not need checksum confirmation already executed!!... # MANUAL MODE#".

 

[BlakeK1287]

My SGH-I997 was doin very vlose to that for awhile. On mine, the power button was stuck, so i took it apart and tinkered wit the button inside and loosened up the plastic one outside. It seems like i read somewhere its somewhat common in these models. Good luck

 

[dt2789]

Remove battery from phone. Hold int button int this sequence. Volume up, home key, power. Phone will cycle one, when you see blue lettering and the top left wait one second then release the buttons in reverse order. This will bring up the factory reset screen. First clear the cache partition, ( navigate using volume keys, and select using power key) then after clearing cache wipe data/factory reset. Once you have done both without any red error messages select onto reboot phone ( first option in list) if you come upon and red errors on the wipe data/factory reset repeat the process of clearing the cache and factory reset until no more red errors

 

[Alzzi]

I tried what you said, but upon pressing and holding the volume up, power and home keys, the phone screen stays black and vibrates periodically. The samsung logo flashed a couple times for a fraction of a second but that's it. I would certainly appreciate any further advice, but I think it may just be time to accept the fact that I have to wait for my new phone.