http://maccaps.com/MacCaps/Repair_books.html

1 - change all the caps

2 - C1 Should be changed with something heavy duty like this http://www.mouser.com/ProductDetail/Panasonic/ECW-FD2W395K/?qs=sGAEpiMZZMv1cc3ydrPrF5m%252btQWx%252bSdKfqDEEG59TPQ%3d

3 - Desolder all the pins of J4 and J2,  Clean/scrub any joints that were burnt/cracked with solder wick and flux and liberally re-solder all the pins  

4 - test it.

5 - if you still get that line then it could be this : Q4