AT&T Merlin 820 Service And Maintenance Manual page 35

How to Select the Correct Procedure
For example, if one voice terminal does not have dial tone, check the
same outside line button on the other voice terminal to see if there is dial
tone.
IF
The same trouble appears on the
second voice terminal,
The same trouble does not appear
on the second voice terminal,
Step 5. Determine if both voice terminals are dead (no lights, no dial tone, and no
response when a button on the dial pad is pressed).
IF
Both voice terminals are dead,
Both voice terminals are not dead,
Step 6. See if the remaining voice terminals in the system are dead.
IF
All of the voice terminals are
dead,
At least one voice terminal is not
dead,
Step 7. The "BASIC TROUBLE TESTS" in this manual entitled "E. All Voice Ter-
minals Have No Lights and No Dial Tone" should be used for this trouble
condition. If you have already used the procedure, call your equipment
supplier for help.
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THEN
Go on to Step 5.
Go to "TROUBLE ON ONE VOICE
TERMINAL."
THEN
Go on to Step 6.
Go to "TROUBLE ON MORE
THAN ONE VOICE TERMINAL."
THEN
Go on to Step 7.
Go to "TROUBLE ON MORE
THAN ONE VOICE TERMINAL."