AT&T Merlin 820 Service And Maintenance Manual page 54

Figure 23—Reconnecting Modular Terminal Cords
Step 8. Place the control unit On/Off switch in the On position. If an auxiliary
power unit is used, plug it back into the ac outlet.
Step 9. Using the voice terminals with intercom numbers that are the same as the
Voice Terminals jack numbers you connected to in Steps 6 and 7 (for
instance, intercom 14 and 19), perform the action that revealed the trouble.
IF
The trouble appears on the voice
terminal that at first had no trou-
ble,
The trouble appears on the voice
terminal that it first appeared,
Step 10. Place the control unit On/Off switch in the Off position. If an auxiliary
power unit is used, unplug it from the ac outlet.
Voice
Terminals
er
10
11
Normal
Area Code
12
Pulse
13
14
Trouble found. It is caused by
the expansion module connected to
this voice terminal.
Go on to Step 10.
Trouble found. It is caused by
the control unit.
Go on to Step 10.
Trouble on One Voice Terminal
20
15
16 21
22
17
18 23
19 24
THEN
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