3Com 7000 manual Port Interface Module LEDs, On LOF is present for at least 5 sec. problems

4-Port Interface Module LEDs 53

Figure 11 DS-3 Status LEDs

Table 13 DS-3 Status LEDs

LED	Color	Description
LOS	Green	On: There is a signal on Rx (normal state).
Loss of Signal		Off: No signal on Rx (problem with Rx).
FERF	Yellow	On: FERF in incoming frames (the peer reports
Far End Rx Failure		about its Rx problem).
Signal		Off: No FERF in incoming frame.
AIS	Blue	On: AIS signal is present for at least 5 sec. (the
Alarm Indication		peer reports about its problem).
Signal		Off: No AIS signal present for at least 5 sec.
		(normal state).
LOF	Red	On: LOF is present for at least 5 sec. (problems
Loss of Frame		with Rx).
		Off: No LOF for at least 15 sec.