I have a Macbook 3,1 (2008, 2GB RAM, Mac OS 10.6.8) with a funny issue.
The original issue was that the computer would boot up, and upon getting to the login screen it would turn off the backlight and would not turn it back on (when you pressed the F button to brighten the display, nothing happened in terms of the backlight, but upon close examination, I could make out that the OS understood what I was trying to do, as I could see the screen brightness logo appear and the bars moving, but no backlight turned on).
I reset the PRAM. That solved the issue, but created a new issue where the fan would run full speed all the time. I downloaded SMCFanControl which showed the temperature at 32ºF and the fan at 000RPM (obviously not the case). Also the battery was not recognized.
So I reset the SMC. That fixed the fan issue, but the original issue with the backlight returned.
Resetting PRAM did nothing this time. The only way to get the backlight to work again was to shutdown, disconnect battery and remove mag safe power cord, hold down power for about 5-10 secs, then, with power still held down, plug in mag safe power cord but still leave battery disconnected, then after another 5-10 secs, then release power, put in battery, and power on the machine. The fan comes on full blast, and the battery is not recognized, but I can see the screen.
So, I can get the machine to run with battery acknowledged and fan working properly, but no backlight
Fan at full blast, no recognition of the batter but ability to actually see the screen (i.e. backlight working).
Does anyone have ideas as to what I can do to get fan working, batter acknowledged and backlight to work?