Section 363-703-103
Revision 01
Page 7
TABLE 3. FLC-703 RT CHANNEL UNIT TROUBLESHOOTING
Indication
Problem
Action
FAULT LED
on
The processor in
the Channel Unit
has stopped.
Remove and re-insert the Channel Unit. If the system does not
restart, replace the Channel Unit.
Troubleshooting based on customer-originated trouble reports
No Dial tone,
Can’t Dial
Short circuit, faulty
COT Channel Unit,
or faulty RT
Channel Unit.
1. Lift the subscriber pair at the RT. If dial tone is present and
calls can be placed, check for shorts toward the subscriber.
2. If you cannot hear a dial tone and/or cannot make calls at the
RT with the subscriber drop lifted, lift the jumper in the CO
between the CO switch and the COT. If you hear a dial tone
and/or can make calls at the switch, try listening for dial tone
on another subscriber pair on a different RT Channel Card. If
dial tone is present on another pair, then replace the COT
Channel Unit and/or RT Channel Unit. If dial tone is not
present on the second subscribe pair, replace COT on RT Line
Unit. Otherwise, the problem is in the CO switch.
Phone
Doesn’t
Ring
High-resistance
short on subscriber
drop, faulty RT
Channel Unit, or
faulty RT Line
Unit.
1. Check for ringing at the RT. If ringing isn’t present on the line
under test, try ringing another line terminated on the same RT
Channel Unit. If ringing is present on other lines, check for
high resistance shorts on the subscriber drop. If no high
resistance shorts, replace the RT Channel Unit.
2. If ringing isn’t present on a circuit terminated on the same RT
Channel Unit, try ringing a line terminated on another RT
Channel Unit. If the line rings, replace the RT Channel Unit. If
the line doesn’t ring, replace the RT Line Unit.
Phone
Doesn’t
Stop
Ringing
Faulty subscriber
station instrument,
faulty RT Channel
Unit, or loop
length too long.
1. Phone stops ringing when using a butt-in at subscriber location:
a) Subscriber’s station instrument’s internal resistance is too
high. Replace instrument according to local policies.
2. If phone doesn’t stop ringing when using a butt-in at the
subscriber location, re-test at the RT:
a) If phone still doesn’t stop ringing, replace the RT Channel
Unit.
b) Otherwise, loop length between RT and subscriber is too long.
Can’t
Hear,
Can’t Be
Heard
Subscriber
problem, faulty
COT Channel Unit,
or faulty RT
Channel Unit.
1. Lift the subscriber drop at the RT. If audible level is acceptable,
there is a problem toward the subscriber.
2. If audible level is too low at the RT with the subscriber drop
lifted, lift the jumper in the CO between the CO switch and the
COT. If audible level is acceptable, replace the COT Channel
Unit and/or RT Channel Unit. Otherwise, the problem is in the
CO switch.
Copyright © 1996, PairGain Technologies, Inc. PairGain is a registered trademark, CopperOptics and PG-Flex are trademarks of
PairGain Technologies, Inc.
