Hi,
Just read your post, then I read the "how to change hdd in iMac emc " in repair section of this site. Came across para.10 which states.... Step 10 — Hard Drive
Before disconnecting the thermal sensor cable, take note of its orientation. It is extremely important to reinstall the connector in the current orientation so the fans will not run at full speed. If you have multiple pins on your replacement hard drive, put the connector closest to the SATA connections and closest to the PCB board.
Disconnect the thermal sensor, SATA power, and SATA data cables by pulling their connectors away from the sockets on the hard drive. "
Do not know if this relates to you but if you installed the thermal sensor with the incorrect orientation it seems to suggest you'll get the problem you're experiencing.
Hi,
Apologies. You were right, I was reading the repair manual for model 2308.
It states
Before disconnecting the thermal sensor cable, take note of its orientation. It is extremely important to reinstall the connector reversed from the current orientation so the fans will not run at full speed.
11 Edit Step 10 — Hard Drive
Before disconnecting the thermal sensor cable, take note of its orientation. It is extremely important to reinstall the connector reversed from the current orientation so the fans will not run at full speed.
Disconnect the thermal sensor by pulling its connector away from the side of the hard drive.
During reassembly, be sure that the thermal sensor connector is connected to set of pins closest to the SATA connectors. If the fans spin at full speed, reverse the connector's position.
It may be that it might also be applicable to your model. The model 2308 only shows 2 wires to the sensor and from what I can see yours is the same. You might try reversing the sensor cable to see if it makes a difference - unless the connector is a one way only fit.
If they are not a one way fit did you disconnect the optical drive sensor cable as well during your HDD replacement? You state that it runs at full speed as well. If you did, try reversing it first and see what happens