Technical data

Overview and Updates
ISDN LED Codes
The ISDN LED codes represent continued power-on and extended self-test testing. If an
error occurs during this testing sequence, a hexadecimal code appears with FRU and error
code information on the monitor screen.
If the system does not enter console mode (>>>) or if hex code DD is not displayed on the
LEDs, use Tables 1-12 and 1-13 to isolate the failed FRU.
Table 1-12 ISDN LED Codes
LED Display Hex Code Solution 1 Solution 2
o•••oooo
70 1 2
o•••ooo•
71 1,3,4 2,5
(M800/M800S/M900)
o•••oo•o
72 1 2
o•••oo••
73 1 2
o•••o•oo
74 1 2
o•••o•o•
75 1 2
o••••••o••••••
77 3,4,1 2
o••••••••ooo
78 3,4,1 2
o••••••••oo••
79 3,4,1 2
o••••••••••••••
7F None: All Tests
Passed

1-15