User`s manual

ADSL
Synchronization
Pass: Indicates that the DSL modem has detected a DSL signal
from the telephone company. A solid ADSL LED on the IAD
also indicates the detection of a DSL signal from the telephone
company.
Fail: indicates that the DSL modem does not detect a signal
from the telephone company’s DSL network. The ADSL LED will
turn off.
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