Test C: 2-Line/5-Terminal Expansion Module - AT&T Merlin 820 Service And Maintenance Manual

Step 23. From one voice terminal, try to make an outside call on each of the outside
lines.
IF
The trouble appears on the same
outside line button as before,
The trouble appears on a different
outside line button,
Step 24. Go to the network interface and switch the two modular cords (see Figure
33).
820 CONTROL UNIT
Figure 33—Switching Modular Line Cords at the Network Interface
Trouble on More Than One Voice Terminal
The trouble is caused by the con-
trol unit or the expansion module.
Put the modular cords back in
their original position. Then, go to
the "Tel. Co. Lines Test" in the
"Test C: 2-Line/5-Terminal
Expansion Module Test" section.
Put the modular cords back in
their original position at the con-
trol unit. Then go on to Step 24.
SWITCH MODULAR
LINE CORDS HERE
THEN
NETWORK
INTERFACE
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