Mac hard drive help

Ok guys. Pretty simple thing, well I hope so. I have the white macbook and got the dreaded dim light. I bought a inverter cable and switched it out. Still did not fix it and made it worse. Before I could flash a light and see items on screen, not anymore.

Ok, so I opened up the mac and did some more research. This entire time I could use the mac on a external screen no problem. I put the mac back together and now it shows the question mark hard drive when I boot. I was thinking great maybe I didn't plug a cable in right. I took it apart and checked everything. Now when I boot I can't see it on the external screen anymore. Thinking I must have messed up the logic board.

Now I took out the hard drive and it's in a external shell now. I see all my applications and everything on there. However for all the apple stuff such as Safari and time machine all have a circle with a slash through it. So my hard drive seems to be ok but all the apple stuff. What is the best solution for me to fix the hard drive?? The OS on the hard drive is 10.7 or so. I'm using a Imac right now that is 10.4 and seeing my hard drive. Do I use disk utlitiy to repair the hard drive??? Please anyone that can tell me how to fix this, I would greatly appreciate it.

 

Thanks guys. Well I went ahead and put the hard drive back in the macbook and now everything is fine. Maybe I didn't put the hard drive in all the way. However, I still have the light going out problem. I am now getting a new inverter board and we'll see how that goes. Everything is working again on a external monitor. Thanks for the help.