Xperia Z won't start

[abeer04]

I tried to update my Sony xperia z C6603 to lolipop through flashtool but it stuck on flashing data.After 2 hours I removed my phone and turned it on but it won't turn on now it say Update failed.Now I downloaded kitkat frimware from xperiafirm and tried to install it again stuck on Checking header.

[Uliwooly]

@abeer04

Download flashtool and a new FTF file > remove both SD and SIM cards > connect your phone to a wall charger > press and hold power & volume up for 10 seconds > let it charge for 1 hour > flash the phone either with flashtool or repair the phone with PCC

[abeer04]

When I press power button and volume up button nothing happens. 

[Uliwooly]

@abeer04

Does it vibrate at all? does the LED turn on?

[abeer04]

@uliwooly

nope no led flashing no viberation my bootloader is not unloacked (maybe that why)

[Uliwooly]

@abeer04

then try this

Connect the phone to a wall charger > press and hold power & volume up for 10 seconds > let it charge for 3 hours > even if it doesn't seem to be working 

[abeer04]

@uliwooly 

Now it viberated once then after a while 3 times and then restart loop sony logo then that update fail error again and again.Should I leave it for 3 hours now o.O

[Uliwooly]

@abeer04

you should.

[abeer04]

@uliwooly

This restarting for 3 hours is giving me chills is it ok to leave my mobile like this 

Spoiler

[Uliwooly]

It's not ideal, could you try a different cable/charger?