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Ben1l

macrumors regular
Original poster
Nov 30, 2006
241
0
Hi all,

The fan on my Mac Pro (Trashcan) Is running at full speed all the time, no matter what it's doing. I've bought a new Mac, but want to sell this one. I've done a complete fresh install of Catalina but that hans't helped. I've taken the fan assembly apart and removed the build up of dust, which helped for about 2 hours, but the fans are now spinning at full speed again.

Any ideas of what I can do to slow them down so I can truthfully sell it as 'full working order'?

Thanks!
 

Selsk

macrumors member
Mar 18, 2017
98
37
Not sure what the actual problem is. I have the same issue with my trashcan. I ran the diagnostics where you hold D on boot. I got 2 errors. Issue with the SMC (PFM006) and issue with the Power Management System (PPN001).

I'm not sure what those are but reseting doesn't help. I just use the Macs fan Control to keep the fans in check. Everything else works as normal.
 

MisterAndrew

macrumors 68020
Sep 15, 2015
2,335
1,768
Portland, Ore.
It's probably some kind of hardware fault. Some people have reported this happening after installing a new CPU. Probably best to take it to an authorized Apple service provider for diagnosis.
 

Selsk

macrumors member
Mar 18, 2017
98
37
It's probably some kind of hardware fault. Some people have reported this happening after installing a new CPU. Probably best to take it to an authorized Apple service provider for diagnosis.
Yes but that sounds very very expensive. I feel like it may have started around the time I changed the thermal paste on the cpu so I might have not tightened something down properly or who knows. I might disassemble it again to have a peek.
 

IowaLynn

Contributor
Feb 22, 2015
2,061
557
Bent pin? too much or not enough thermal paste, in which case take a peek. And whether it is a known issue with that processor in "trash can." Exchange or try with a 2nd cpu.
 

MisterAndrew

macrumors 68020
Sep 15, 2015
2,335
1,768
Portland, Ore.
Yes but that sounds very very expensive. I feel like it may have started around the time I changed the thermal paste on the cpu so I might have not tightened something down properly or who knows. I might disassemble it again to have a peek.
This makes sense now. I'm sorry that happened. These machines are delicate. Repairs require special equipment and knowledge. Do you have a copy of Apple's technician guide? It's posted in another thread with "LED diagnostics" in the title or you can buy it from a seller on eBay. I suggest to not follow the directions in any YouTube video or other non-Apple source. Follow Apple's instructions only.

Make sure the exact torque specs are observed. You'll need to get a torque screwdriver if you don't have one. Also pay careful attention to the flex cable routing. It's possible it became kinked or damaged during re-assembly. Apple's instructions include photos of the correct and incorrect routing.

Apple may not charge you that much to fix it. I've heard people have gotten away for about $500 with a logic board or GPU replacement.
 
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h9826790

macrumors P6
Apr 3, 2014
15,351
7,622
Hong Kong
Yes but that sounds very very expensive. I feel like it may have started around the time I changed the thermal paste on the cpu so I might have not tightened something down properly or who knows. I might disassemble it again to have a peek.
If there is any Apple store around, take it to have a check, checking is free.
 

iliyan61

macrumors newbie
Mar 20, 2020
10
2
make sure the CPU is properly tightened down properly but its not a huge deal IMO just use macs fan control rather then wasting 5+ hours and more money on it.
 
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