Could be a few reasons for what this problem is. Re-seating the invertor is not going to make a difference but replacing it may actually fix it and for the cost of about £6 - £12 it may be worth replacing it to fix it.
Most laptops are all very similar put together, and striping them down is a similar standard process.
I used this when I started out and now I can strip laptop blindfolded (well not quite)
Click on the small pics will expand the pictures so you can look at them better