Editing Macintosh HDD Maintenance (section)

=== Remove the terminator resistors ===
'''Apple's caution is explicit: "failure to remove the terminator resistors can damage the
logic board."''' Service replacement drives shipped terminated, and the terminators have to
come off before the drive goes into a machine that terminates elsewhere.<ref name="hdss" />

* On the 160 MB drive, pull up on the tab to lift the resistor pack out.
* On the 230 MB drive, use needle-nose pliers and pull the resistors straight up.
* On 5.25-inch external replacements, disconnect the resistors from the component side, again pulling straight up.

Watch the orientation of the SCSI select cable as well: Apple specifies tab-up on the 160 MB
and 230 MB drives and tab '''down''' on the 400 MB drive.<ref name="hdss" />