Impossible to enter fasboot mode
First, please forgive my english, i'm french.
I've got a Xperia ion with which one I'm trying to unlock bootloader. The phone is already rooted.
I followed the XDA topic to do it but I've got a problem when I try to put my xperia in fasboot mode.
When I put the volum + button to put it into fasboot mode, my phone reboot, the blue LED is on but after 5 or 10 secondes, it stops and the phone boot normally. What I'm trying to say is that I can't keep the fastboot mode more than a few seconds.
I've downloaded all the driver.
Do someone have a solution for this problem ?