Hi!
First
Make sure connections.(Power and data cable) are in the right possition.(if you have only one disk drive (DD) use a single data cable not for two disk drives)
Second
When you turn on the A2K, there must appear the kickstart screen whit the hand and a disk, if not maybe this the problem. If it's appears make sure that the DD makes a "click" continously. If ther is no noise the DD is without power or broken.
Thirth
Try to clean heads on the DD with a ear stick and alcohol (BE CAREFULL) only with a light force and move manually the main motor (in the botom of the DD a big metallic disk)
Fourth
If it don't work, replace it.
Rrete :idea: