A1707 Macbook fan at full speed

[Roll]

Hello guys, I have this Macbook Pro with touchbar and it's acting up.

First it came as completely dead - I found out it was one of thunderbolt controlers. I removed it, laptop came back to life, but one fan was loud. I didn't have replacement IC, so I thought it was in panic mode or something.
Then new IC arrived - I replaced it, but it still is in full blast mode.
It gets to full speed right after pressing the power button.

I tried reseting the SMC and PRAM - no change.
I installed Fan control app - all temperatures are OK, right side fan works fine, but left one is stuck at highest RPMs. When I try to set it any lower, it does not react at all.


Is there anything I can do about this? Thanks

[mon2]

Re: A1707 Macbook fan at full speed

Swap the fans to see if the good right fan runs in hyper speed on the other side (left).

Check the pinout of the fan cable in the schematic before proceeding.

Also see here

https://youtu.be/MgPighrnTA0

-- another link on ifixit blamed the fan itself