Chosen Solution
This one has me stumped but it’s late in the day. Apple iMac “Core i3” 3.2 27-Inch (Mid-2010) Specs Mid-2010 - MC510LL/A - iMac11,3 - A1312 - 2390 16GB RAM Installed a Samsung 860 1TB EVO OWCINSIMACHDD09 Hard Drive thermal sensor Blew it all out, not bad dust for one this old. Everything worked great no problems, very fast. No fan issues. Buttoned her up. Cleaned exterior correctly. Zapped the PRAM for final delivery. Now have racing CPU & ODD fans, hard drive fan is fine. It is not coming to me why this is happening.
@danj any thoughts? UPDATE 9/23/19 Opened it back up and ensured all connectors were secure. Booted up several times and no problems. Run youtube videos for two hours. Delivered machine. Customer says TG Pro reporting racing CPU & ODD fans, hard drive fan is fine.
@mayer - Did you take the logic board out? Could you have plugged in the sensor into the wrong connector?
