IBM 9080-M9S Manual page 509

Figure 438. Replacing the UPIC cable into the system control unit
c) Push the white plastic lock (B) onto the plug housing as shown in the following figure.
Figure 439. Replacing the UPIC cable into the system control unit
d) Lightly pull on the UPIC cable from both attachment points to ensure it is locked into place. Pull the
cable connector; do not pull on the wire. The cables should be firmly attached to the system.
Power interface card 503