AT&T MERLIN LEGEND Communications System Release 2.0 Maintenance And Troubleshooting Manual page 97

Control Unit Problems
8.
Disconnect the other cable from the header labeled P101 on the right
side of the power supply circuit board.
NOTE:
As shown in Figure 4-2, you need to grip this cable firmly and pull
forcefully.
9.
Remove the four screws from the ring generator as shown in
Figure 4-2.
10.
Remove the ring generator.
11.
Position the replacement ring generator as shown in Figure 4-2 and
align the screw holes.
NOTE:
Make sure the P1 header on the ring generator is on the same side
of the power supply housing as the P1O1. header on the circuit
board.
12.
Replace the four screws and fasten them to secure the ring generator.
13. Connect one end of the new ring generator's cable with the 3-pin
connectors to the header labeled P1O1 on the power supply circuit
board.
NOTE:
This cable connector, as with all four of the cable connectors, is
keyed so that you cannot attach it to the header if it is turned the
wrong way.
Power Supply Problems 4-7