I currently a MBWE II with a single TB drive (I will be upgrading to a second drive shortly). I have followed all the steps but the fan still does not come on except during startup and if I change the value in /sys/devices/platform/wdc-fan/speed.
When I manually change the value the fan comes on for a minute or so and the value automatically gets set back to zero and the fans shuts off. I assume the temp monitor script is setting back to zero.
hdparm v6.5 has been installed via Optware and I changed the HDPARM location temperature_monitor file to: