820-00850 Runs slow, fans 100%

[hambook]

Hey all, have a 820-00850 board on my desk right now that came in with liquid damage, was stuck at 5v. Replaced a liquid damaged CD3215 and a few surrounding components and now board turns on and boots. When it gets to the OS the mouse is very laggy and the fans spike up to 100%. AHT reports no issues. Wondering where to start on this one.

 

[2informaticos]

You should try known good trackpad.
Try first disconnecting LCD connector, using external monitor.
Or just disconnecting the webcam...

 

[hambook]

Tested with just the logic board itself outside of the case plugged into external mouse/kb/display with LCD connector removed. Same laggy mouse and very slow unfortunately.

 

[2informaticos]

If INTERNAL trackpad is not connected, this behavior is normal.
It has thermal sensors, required by SMC!!!

 

[hambook]

Did not know that! I'll test again with a new trackpad and cable.

 

[hambook]

This one is officially stumping me, have tried 2 known working trackpads/cables with all else disconnected and still get slowness/high fans

 

[2informaticos]

Did you test with known good trackpad board/flex and webcam disconnected?

 

[hambook]

Correct, the trackpad and flex I'm using to test work fine in another unit I have in. LCD flex is completely unplugged from LB, I'm testing with external video

 

[2informaticos]

Check the temperatures reported by HWMonitor.