Fan stuck at full speed

"James Gordon



Rep: 97




1


1"

"Kyle,

One thing to check is the print manager. Sometimes the CPU gets stuck on trying to print to an unconnected printer.

Go to

Finder> Utilities> Activity Monitor

Select display all processes

Find the process taking up the most CPU % and kill that process.

The fan speed should drop within seconds.

Let us know.

Frank"

"I had this fan spin issue on my older core 2 duo mac mini, after installing an ssd. I solved this by replugging the fan in proper orientation. I must have turned it around during reinstallation.

Possibly this is a solution here also."

"I have resolved my fan issue. A surface mount component had somehow come off the logic board and as a result the (pwm) fan control signal was not controlling the fan. The fan defaults to full speed when it sees no pwm signal. I was able to see the (monitor) signal was working by using smcfancontrol and the slowed the fan with my finger - the rpm changed. As a result the mac was requesting, for example, 2000rpm, but as the fan didn't see the request it was giving approx. 6500rpm, hence the error code. The missing component was a bridging SMD device. By hooking up an oscilloscope I could see a pwm signal on one side of the missing bridge, but no signal at the fan. As soon as the 2 pads were bridged normal service resumed. Not sure how this component has become detached, presumably when I removed the fan connector.

Anyway, it is worth checking for 2 solder pads just above the fan connector - if you see no component then you may have the same issue!"

CREATE THIS ON AUTOMATOR /applications/smcfancontrol.app/Contents/resources/smc -k F1Mx -w 1770