Installation and Test
363-754-104-01, Revision 01
10
June 22, 1998
PG-Flex FRC-754 List 4
Troubleshooting
provides troubleshooting procedures based on indications displayed by the front panel indicators of the
FRC-754 List 4 channel unit.
Table 10.
FRC-754 List 4 Channel Unit Troubleshooting Procedures
Indication
Problem
Action
FAULT LED ON The FRC-754 processor has
detected a fault.
Remove and reinsert the Channel Unit. If the FAULT LED does not extinguish,
replace the Channel Unit.
Troubleshooting based on customer-originated trouble reports
No Dial Tone,
Can’t Dial
•
faulty RT or COT Channel
Unit
•
facility short/open
•
CO switch problem
•
Tip/Ring reversed at CO
1
Lift the subscriber pair at the network interface. If dial tone is present and you
can place a call, refer the problem to the customer per local practice.
2
If you cannot hear a dial tone or cannot place a call at the network interface
(with the subscriber pair lifted), check for a dial tone at the RT. If a dial tone is
present, check the pair between the RT and the network interface. If no dial tone
is present, replace the RT Channel Unit.
3
If the problem still exists, reinsert the original RT Channel Unit and replace the
COT Channel Unit. Test for operation.
4
If the problem still exists, refer the problem to the CO switch.
Phone Doesn’t
Ring
•
high-resistance subscriber
line short
•
faulty RT or CO Channel
Unit
•
loop length too long
1
Lift the subscriber pair at the network interface. If ringing is present, refer the
problem to the customer per local practice.
2
If ringing is not present, check for ringing at the RT. If ringing is present, check
the pair between the RT and the network interface. If no ringing is present,
replace the RT Channel Unit. If ringing is still not present, check a circuit on
another Channel Unit. If ringing is still not present, replace the RT Line Unit.
3
If ringing is still not present at the RT, reinsert the original Channel Unit and
Line Unit. Test for ringing at the COT.
4
Test for ringing into the COT from the CO switch. If no ringing is present, refer
the trouble to the CO switch. If ringing is present, replace the COT Channel Unit.
Test again for ringing at the network interface. If ringing is still not present,
contact PairGain technical assistance per
.
5
Verify the resistance of the copper loop between the RT Enclosure and the
network interface is less than 530
Ω
.
Phone Doesn’t
Stop Ringing
•
faulty subscriber
instrument
•
faulty RT Channel Unit
•
loop length too long
1
Test for ring trip at the network interface. If the ringing is tripped, refer the
trouble to the customer per local practice.
2
If the ringing is not tripped, test for tripping at the RT. If ring trip does occur,
check the loop for excessive length. If ring trip does not occur, replace the RT
Channel Unit. If ring trip still does not occur, contact PairGain technical
assistance per
.
3
Verify the resistance of the copper loop between the RT Enclosure and the
network interface is less than 530
Ω
.
Can’t Hear,
Can’t Be Heard
•
subscriber problem
•
faulty RT or COT Channel
Unit
1
Lift the subscriber line at the network interface and check the signal level. If
correct, refer trouble to the customer per local practice.
2
If the level is too low, check the level at the RT. If the level is correct at the RT,
check the pair between the RT and the network interface. If the level is too low
at the RT, replace the RT Channel Unit.
3
If the level is still too low, reinsert the original RT Channel Unit.
4
Check the level at the COT coming from the CO switch. If it is correct, replace
the COT Channel Unit. If it is not correct, refer the problem to the CO regarding
the switch.
5
If the level is still not correct, reinsert the original COT Channel Unit. Contact
PairGain technical assistance per
.
Summary of Contents for PG-Flex FRC-754 L4
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