Attempted backlight repair causes keyboard to stop working.
I acquired an early 2009 Macbook a1181 with a backlight issue; the backlight will flick on at boot and then die. The backlight has also momentarily turned on whilst adjusting the brightness. First, I tried to replace the display inverter, which had little effect. However, I did manage to get the backlight on for a couple of minutes with a little fiddling, holding down the inverter cable may have helped? I've never managed to get the backlight on for any length of time since.
Suspecting the inverter cable, I opened up the Macbook again to take a look. I put it back together again, and it wouldn't boot at all. I eventually found the cause to be a dead keyboard, trackpad and power button, as the laptop turns on when the contacts on the motherboard are shorted. There is no viable damage to the keyboard ribbon, and the socket on the motherboard seems fine too (I've looked closely with a magnifying glass).
What I would really like to know is the best way to remedy both of these problems as inexpensively as possible. Would it be a good idea to purchase a new inverter cable and keyboard cable or should I buy a 'parts' machine on eBay?
Please let me know your thoughts and what you think is causing both of these problems.