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Article Id 195277
In the event of an ADSL connectivity failure there are some steps which can be taken to confirm the root of the issue that has brought the ADSL service status down.

One possible cause is an actual physical failure that sometimes cannot be detected by an HQIP test.

FortiWiFi-60CA using ADSL port

1. By having the interface connected to an ADSL modem run the "diag debug application adsl2 255" command.  Confirm ADSL status is DOWN:
Day Mon Dat HH:MM:SS YYYY 60soc_adsl.c[686] adsl2plus_check_status - ADSL's link is down

2. Proceed to run the "diag adsl show 2" command.  If the "Modem Status" is "SHOWTIME_TC_SYNC" it is not a hardware module failure:
Modem Status                        [SHOWTIME_TC_SYNC] 

If the "Modem Status" is "SILENT" there may be a physical link issue or ADSL module hardware issue:
Modem Status                        [SILENT]

3. A further test should then be made with another device being connected to the ADSL modem in order to confirm the connectivity status.   If the status is also "SILENT" then it is a physical link issue.  Otherwise it may well be a FortiWiFi ADSL module hardware failure and it should be replaced by an RMA exchange.