If you’ve hard bricked your Galaxy S2 (and can’t get into download mode) or you want to reset the ODIN download counter (so no one will no you’ve rooted your Galaxy S2), or you just simply
want to remove the i9100 splash screen, you can make a USB jig to solve all your problems.
What is a USB jig?
USB jig is a simple circuit that allows you to reset the download mode and also get into it for Samsung smartphones (can work on other Samsung phones besides the Galaxy S2) just in case something goes wrong. On a hard brick, this can save your phone as it will enter into download mode. Think of it as a reset switch.
You can buy a USB jig on Amazon for around $6-10 or for about $2, you can make your own. It’s a really simple circuit that involves putting 300K Ohms of resistors between pin 4 and 5 of the microUSB connector.