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I spilled a little water on the keyboard and immediately dried it out. The laptop functioned perfectly fine after. I was worried that there could be some water deep inside so, a couple days later, I removed the logic board to clean underneath it. There was not any water there. I used canned air to clean out dust, and a hairdryer to make sure there was no water. After reassembling, the left fan has been stuck at full speed whenever the computer is running. I did not remove the fan during this cleaning. I am using iStat Menus. The thermal sensors appear to be fine.
I am able to use iStat Menus to set the fan speed for the right fan but the left does not respond to the controls. I tried resetting the SMC and PRAM. I ran an Apple Diagnostics and it said there may be a problem with the fan. I installed a replacement fan and the problem still persists. What can I do to get the fan under control? Could the heat from the hair dryer have damaged the fan connector or its circuit?
I seriously doubt canned air would have damaged anything on the logic board..fact is that even if a small amount of water reached the board it might have shorted out a secondary but certainly not useless component. Fact is that due to the size of parts it’s hard to see anything with less than 10x magnifying and often one can’t see anything at all and just needs to test power/data lines. If it spins full speed and a replacement fan and smc reset didn’t help it’s likely the fan speed control data line or related component got damaged. I’m afraid you’ll need a component level repair professional here.
Hi! I have the same issue and I found out one of my transistors, more specifically Q6050 was mising from my board. It was yanked out most probably during reassembly. (Oh yeah, and a resistor too)
As you can see the trio of black resistors and the transistor in between should be complete each fan but the one at the bottom has missing parts.
The transistor is the black block while the resistors are the silver ones with a black middle. I’ve ordered these parts online and I’ll get back if it fixes the issue.
You’ll need to run the onboard diagnostics to see what it tells you. Restart your system and hold the D key. That will get you in, once you get an error code let us know. Depending on what you get you may need a new fan or you forgot to connect something. Reference: Mac startup key combinations
i have mid 2015 15” Macbook Pro, its right fan is showing 5700 rpm max but left one is 6156 rpm max at mac fans control app. Shouldn’t they be at same rpm? Or is it normal as default?
I already bought the missing parts but the problem is I need quite a bit of skill as well as a hot air workstation. Hopefully someone would be able to fix theirs using the info below: Here is the fan control circuit on the board (It’s missing a MOSFET-[Part#Q6050] and a Resistor-[Part#R6051])
Here’s the location of the parts on the board
Here’s the diagram for the fan control circuit
Finally, here’s the parts that you need (They’re really tiny haha)
In A1707 the location of the mosfets is right under the keyboard connector (oposite side of PCB). In my case the components were still there, but the left fan was running at full speed all the time. Did a reflow (apply solder paste and then hot air with SMD solder station) but it did not work. So, I bridged the Drain pins of both mosfets and now both fans are controlled by the right side driver. There are test pads for the Drain pins, so solder is easy by bridging those pads. The laptop seems to be working fine with both fans controlled together, but you can install Mac Fan Control or similar app to assign more sensors to drive the good mosfet.
I’ve had the same issues plus gradual disappearance of thunderbolt ports functionality for a couple of years. And I resolved those all just today by replacing the original ports with couple of ones from AliExpress. To be honesty, I was afraid to completely break the device, and when I booted after replacement and have still been seeing same issues, I’ve thought “at least it is alive” and go for a rest. After a couple of hours without any resetting of SMC or PRAM it shouted up the fans (silence! finally!) and gradually kick up the ports so I finally can use HDPI 4K@60Hz, full-speed external hard drives and firewire audio interface via thunderbolt. It is epic win for just a $20! \ 0 /
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