Answer to: CPU Fan runs at full speed.Update on my situation: Ordered the correct resistor based upon this diagram http://lkcomputers.com/janhoffmann/Apple...-7863-A.pdf a "47K 1/16W 5% in a 0402 package." Had a friend solder the little guy onto the board right above the power button connector and it totally solved the problem. Looks like it's really easy to break that resistor off while plugging that cable back in. Probably pretty impossible to even realize it happened because of the size.
Answer to: CPU fan full speed showing 0rpmI would check to see if you lost a resistor in the process. Seems common that if you have a CPU fan which reads 0 rpm but seems to be going full blast, there's likely an issue with the circuitry on the logic board. What a few people have found in another thread is that there's a 47KΩ resistor which is missing near the power button connector. If you have one missing from there, all you need is a new resistor and your Mac will function CORRECTLY because it knows the fan speed. Link: CPU Fan runs at full speed.