I found that when changing the HDD to take the pcb board off the new drive and remove the upper section of the plug with needle nose pliers. This allow the tab on top of the temp sensor to fit into the plug of the new drive. If you look at the original drive you will see the notch that allows the plug to be inserted. Notch is like the notch on ide cables. I just did this on over 100 2010 imacs and have had no issues. Dept of Education Imac tech