Compaq TA1000 Reference Manual page 53

7. While grasping the I/O module handle, press the I/O module latch 1
down and push the I/O module into the enclosure until it is fully seated.
8. Connect the cable connector to the same connectors (see Step 4).
9. If power was removed in Step 2, apply it to the enclosure.
10. Activate the SCSI bus and observe the LEDs to verify that the I/O
module is functioning properly.
Customer Replaceable Units 7-11