Data recovery and disk repair questions and discussions related to old-fashioned SATA, SAS, SCSI, IDE, MFM hard drives - any type of storage device that has moving parts
Without power applied, plug the adapter into the HDD. Using a multimeter, test for continuity between a ground point on the adapter and a ground point on the HDD PCB (eg a screw hole). Invert the adapter and repeat the test.
For additional confidence, repeat the test for the +3.3V test points. The +3.3V pins on the HDD side should be identifiable by their thicker power traces.