Chosen Solution
Hello. Just replaced thermal compound on 2015 macbook pro. Upon restart the fans slowly ramp up to full and the computer runs slow. Also diagnostics is saying SMC issue. with code PFM006. I’m trying to identify the temp sensors. are they the round spongy things to either side of the CPU and graphics chip? Update (05/12/2022) Hi Dan. I already own iStat Menu and can give you a screen shot from that. pretty sure it lists all my fans and temp sensors.
Update (05/13/2022) Ok, downloaded the trial version of TG Pro. Results look the same as iStat Pro. Looks like all temp sensors are reading valid results, but computer is running painfully slow, and fans running at full. Any suggestions appreciated. Thanks!
I believe my logic board number is 820-3787. However I got this number by referencing the model number and EMC number. Without removing the logic board I am unable to find any number that is formatted 820-xxxx. Other info that may or may not be relevant. Mid 2015 retina Macbook Pro 2.5 GHz. 16 GB ram. 250 GB SSD. Model A1398 EMC 2910 I can also give the serial number of the computer if that helps at all. Thanks!
So, The Apple Genius did his thing and found absolutely nothing wrong with the SMC according to their in house testing. He did find an error with the SSD, or the SSD socket. However he also noted that it seems to be working fine even though it shows an error. When the computer was being tested the fans did not spin up to full speed either. Now that I have it at home its again giving an SMC error when I run diagnostics, and the fans are running up. So, No real answers for all my efforts. The Genius concurred that the thermal paste replacement I did wouldn’t cause this. So it may be an intermittent problem and the seller knew this, hence the fairly good price I got it for. I’m going to buy a logic board. It would be required for either of the above errors. It seems whatever is going on that should fix it. Thanks for everyone’s feedback and help on this issue Keir
Well, your issue is not a thermal sensor issue as all of the sensors are woking! It looks like you have one of the current/voltage sensors failing which is why your systems fan is ramped up and the CPU’s clocking is reduced (CPU Safe Mode). I would inspect your cable connections and make sure you haven’t damaged the connectors both cable and logic board.
@Keir Briscoe can you post another picture just a nice clean close up of the area I’ve marked (red)? Remove the covers or flip them up (blue) so we can see the components under it. Something odd there….or just my old eyes. Just out of curiosity why did you change teh thermal paste? Anything transpired to make you do it?
Update (05/18/2022) Okay so the temperature sensors are pretty much on the other side of your board. Since you did not move it at all etc. it is unlikely that those are at fault but you asked for it :-) GPU PROXIMITY/GPU DIE/LEFT FIN STACK/RIGHT FIN STACK Reference designator U5850 DDR3 PROXIMITY/CPU PROXIMITY/PCH PROXIMITY/AIRFLOW PROXIMITY Reference designator U5870 X87 PROXIMITY Reference designator U5823 TBT DIE Reference designator XW5820
