I have an iphone 3gs which I jailbroke months ago with blackra1n. yesterday suddenly the screen went black. nothing works. pressing home and power buttons just makes the apple logo appear. when connected to charger or mac sometimes the charging screen will appear but won't charge. canīt get it to work. when connected to mac, itunes does not open. I've tried to hold both buttons for long time, then just one of them, then none, again both.
thanks in advance