AT&T Merlin 820 Service And Maintenance Manual page 98

Step 2. At the control unit, switch the modular line cord plug of a line known to
be working with the plug of the line cord connected to the line-powered
alert (see Figure 48).
TO NETWORK
INTERFACE
TO NETWORK
INTERFACE OF
WORKING LINE
Place a call using the line known to be working. If the call can be com-
Step 3.
pleted, then have the person you called return your call using the tele-
phone number of the line known to be working.
The call cannot be completed or
the person was unable to return
your call,
The call can be completed and the
person was able to return your
call,
SWITCH THE PLUGS OF THE
MODULAR LINE CORDS HERE
LINE-
POWERED
ALERT
Figure 48—Line Cord Plug Switch
IF
Trouble on an Accessory
THEN
Trouble found. It is caused by
the control unit or expansion
module connected to the line cord
known to be working. Go to the
"Tel. Co. Lines Test" section of
"TROUBLE ON MORE THAN
ONE VOICE TERMINAL" to
determine which component is
causing the problem.
Return the cords to their original
positions, then go on to Step 4.
CONTROL UNIT
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