Apple A Day
Backlight switching off at certain positions of the lid.
I have a 2008 MacBook Core2Duo A1181 White 2.4 GHz. My backlight seems to switch off at certain positions of the lid. It started off with a very narrow range and within a few days it is switching off at much wider angle. However, the weird thing is that the range of "backlight off" is changing every day.
I have already tried a SMC reset and a NVRAM/PRAM reset and it did not help.
Based on further research I have concluded that it is quite likely a case of the cable connecting the main logic board to the LCD going defective. It works fine on an external display.
However, before I order a part, I want to make sure it is the right one. Plugging my serial number on to some websites have made me believe I have a Penryn core.
Now, if I want to try replacing the cable connecting the LCD to the MLB, which of these two should I get:
Which of these two is the one that passes through the left hinge and hence has a higher likelihood of being damaged from normal use? The macbook had never been dropped, but have been used for thousands of hours and has been opened and closed thousands of times.
And, finally, is there a chance it could actually be the inverter board which might be malfunctioning? If so, is there a way to find out if it actually is?
You need an inverter cable, not a video cable, if you see a faint image and the backlight goes out when you flex the hinge. The inverter system (screen, inverter cable, inverter, board) is responsible for the light. You're lucky you have a 2.4GHZ, because that is the only speed machine that it is possible to determine the correct inverter cable for without further examination of the board -- you need the "Santa Rosa/Penryn" inverter cable you list above. This has a 3-wall connector on the logic board side, whereas earlier A1181 boards have a 4-wall connector.
In some cases you take off the topcase and open the hinge, and alleviate the stress point which was causing the cable to be crimped, and then save yourself buying a new cable, but in most cases you'll need a new cable.
There's a slight chance your screen is going out, but given what you've described, the inverter cable is the most likely culprit.