Hi,
Good luck trying to repair it.
You would be better off replacing the part.
Here are some links for the replacement part.
It depends on how long you wish to wait as to how much you wish to pay.
http://www.etradesupply.com/sony-xperia-zr-m36h-motherboard-flex-cable-ribbon.html
http://www.ebay.com/itm/Original-Motherboard-Flex-Cable-Ribbon-For-Sony-Xperia-ZR-M36h-/271833407699?hash=item3f4a88a0d3:g:dywAAOSwNSxVJiwM