Faulty Electronics on Buzz Lightyear Deluxe wings jet pack?

Hello -

I recently bought a Buzz Lightyear Deluxe retractable wings jet pack from ebay. Only when I received it, it didn't work, these are a deleted item now that you can no longer get. So I am looking at the possibility of repairing it, I have had it open & as far as I can see everything is connected ok, although I have thought about re-soldering all the electronics on again, there are three thing the toy should do - wings open & fold electronically, lights at the end of the wings light up & you can hear phrases from buzz lightyear, none of these functions work at all. The only thing that happens is when the function button is pressed, you can hear a slight crackle at times from the speaker, but that's it. Any help with this would be brilliant, maybe some tips or places I can try to get it fixed?? Please help!!