ALARMS, TROUBLESHOOTING & TESTING
11
4. 2 Troubleshooting
Step 1: Establish and verify the E3/DS3 WAN link
Check the status LED on the rear panel of the unit at both ends of the link. If either is OFF,
power is not present on that unit. Check the mains connection to the unit. If mains supply is
satisfactory, we recommend that the unit be taken out of service and returned to a repair
centre. Unqualified users should not open the DC3445 .
LINE BNC connectors
If the status LED is
RED
or flashing RED/O
FF
, try swapping the LINE BNC connections at
that unit. Also check that the E3/DS3 Mode bit-switch has been set correctly.
If the status LED remains red or flashing red/off, try looping the BNC connections on the unit
with a short piece of cable. If the status LED goes steady green or flashes green/off,
then the external BNC cabling is faulty. Check for cable continuity and network connections,
etc.
Step 2 Establish and verify the DTE link
If the status LED flashes
GREEN/OFF
, check that the local router port status is
UP
and that
the local router cable is in place.
If problems persist, check the DTE cabling configuration. Running
TEST LOOPS
will help to
isolate the problem area - see next section. Transmit and Receive data connections may be
crossed, as may any of the handshaking and/or signalling lines.
Step 3: Bridge/Router configuration
As the DC3445 is used in a variety of locations and with many different manufacturer’s
equipment it is impossible for us to cover all eventualities here, so please consult other
manufacturer’s operating manual for further information.
