Hi, You short the lcd connector when plug in the main board. 2 diods (called D8228 & D8258 //pmeg 4010bea sod323 -cost app. 0,5$ for each) and/or 2 coils shut be burnt. If not, next two parts are L7080 & L7085. Cost app 0,5$ for each. If You know some about microsoldering - repair is easy and shut cost few $. If not, take of m.board from and go to electronic repair shop. Cost... 15-20$. Cost of repair apple serw. or phone street rep shop- 120$ diagnostics and 150$ repair :) If you get this way- more better is sold as is on ebay and buy brand new.
Hi, the problematic part is called U2301. U have to de solder chip and make a jumper between leg 1&2 (for fast repair -aprox 5 min) Second method is change U2301 for brand new : ( http://www.ebay.com/itm/1PCS-U2301-Camera-Power-Supply-2-8V-4-PIN-Tube-IC-Chip-for-iPhone-6-6-plus-/291830904214?hash=item43f27a3596:g:vykA... ) -for example.