AT&T MERLIN LEGEND Reference page 110

M a i n t e n a n c e
Step Screen Display
1 0
Demand Test Slot xx:
Board 800 CO-BRI
Internal Loopback Test
FAILED
Xxxxxxxxxxxxxxxxxxxxxxx
xx xx xx xx xx xx xx xx
Exit
After the test is run, restore the 800 CO-BRl module and exit maintenance as you
would for any demand test (see the Maintenance and
#555-620-143).
Board Controller Test
The Board Controller Test checks the circuitry, firmware, and other electronic
elements of the 800 CO-BRI module. If the module fails the test, it usually should
be replaced. If the test fails during the firmware test, one or more of the following
messages appear on the MLX-20L telephone or PC display:
Boot ROM Failure
RAM Failure
Timer Failure
Transceiver Failure
HDLC Failure
Flash ROM Failure
Dual Port RAM Failure
Procedure
If the test fails, you receive error
messages and error counts.
Troubleshooting Guide,
Demand Tests
6-7