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After doing a hardware test (the quicker of the two), I came up with this error code. ’’’ 4SNS/1/40000000:TCOD’’’ I have Googled it and I keep coming across temperature sensor articles or people with kernel dump issues. The latter doesn’t apply as there are no software or stability issues. So the temperature sensor(s) is either faulty or not connected. This would kind of make sense, as the fans do run heavy, even if the mac book isn’t doing particularly much. Is there a guide on how to replace/repair said temp sensors? Although I have installed ISTAT MENUS but all of the temperature readings do actually have readings. So they must all be connected, surely? Any suggestions people? Thanks in advance.
The TCOD at the end of the error code denotes it is the temperature sensor for the CPU. These thermal sensor error codes can be triggered for a number of reasons, bad temperatures (hot or cold), wrong current or voltage going to them. Try resetting your SMC. Instructions for that are here: http://support.apple.com/kb/ht3964 and let us know if that solved your problem. I also suggest you run the extended hardware test to see what if anything it comes up with. Why did you run the hardware test? What are the temps and fan speeds in iStat at idle and under load? What are the last 3 characters of your serial number so we can determine your exact machine? Added with edit With the CPU temps you are giving your processor is running hot, by at least 10C. I highly recommend that you replace the thermal compound/paste on your CPU & video chip. The Arctic Silver thermal paste, available here, is what I use. It typically lowers chip temperatures 5C - 10C under the same load conditions. You only want to apply a very thin coat of the stuff - enough to cover the chip but not squeeze out when the heatsink is attached. The gist of the instructions for applying thermal paste are here. To apply the thermal compound you will need to remove the heatsink. Instructions for doing that are here. You also may want to clean your heatsink and fan while it is apart.
