W580i camera fault - 'Open Phone' message

Hi everybody ,
I'm not sure if this is the right place to post this in,if its not I do apologise.
I'm after some help to repair my sons Sony w580i.
Originally he dropped it and at the same time crushed it in our car's door.It ended up out of shape and with a cracked screen
I bought a new screen stripped the phone down straitened the slider replaced the case and screen put it all back together and all appeared fine until I discovered that the memory card holder would 'lock' the memory card.So I then bought a new ribbon cable which had the memory card reader,camera socket, and top buttons membrane (sorry I don't know whats the correct name for this).I then stripped the phone down again and replaced the the above ribbon cable.
Now the phone as far as I've tested is all OK except that when you slide the phone up and select camera it says on the screen 'open phone' when obviously it already is.
Also if you select slide to answer a call / finish a call that doesn't work and the lower (number) key board doesn't light up when you slide the phone open (they light up when you first turn the phone on).These two faults along with the camera fault all seem to be related to the phone not knowing its slid open.
I've been to the sony site and downloaded the firmware incase it got corrupted but that didn't make any difference?
The camera worked when I first repaired the phone.
What senses or detects on the slider that the phones open I can't see anything obvious.
I'm beginning to think it would have been cheaper to buy a new phone!
Is there anyware to get a manual with faults and fixes for these phones?
Any advice gratefully received.

I didnt drop mine but after trying to update my firmware, I got the same problems as you. I bought a new main ribbon cable but I am stuck trying to get the rear PCB board off. Once that is off I can replace the cable and I will let you know if it helps.

change flex cable.

try changing the flex slide (L) is common your situation and the problem presented is direct damage to membrane.

Hi, my w580i has a problem in camera. once shows some disturbance on screen when i press the upper side of camera it works fine, next day it did the same. i open back side and apply little pressure on the side of lens then it start saying another application is running close it and some time when i switch on camera, mobile get held.
help needed