Instruction manual

No. Symptoms Probable Cause Corrective Measures
5 TEST flashes
SYNC LOSS off
Configuration error Check for the following possible errors, and
correct if necessary:
– Both the local and remote DV-MUX3 are
configured as slave units.
– Both are configured as master units, and the
parameters are different.
– Both are configured as master units, and the
MODE jumper settings are different.
– Both are in remote loopback in the same
channel
6 SYNC LOSS lights
intermittently
Receive clock and
transmit clock are not
from the same source
If the modem on one side is set to transmit
timing, the modem on the other side must be set
to loopback timing.
7 TEST off
SYNC LOSS off
The local voice channel
voice user cannot hear,
and/or cannot setup
calls.
Local data channel
operates normally
1. Incorrect selection of
voice channel interface,
or problem in the
channel connection
cables
Check that the proper interface is used: an FXO
interface must be connected to a PABX, an FXS
interface must be connected to a telephone set,
and an E&M interface must be connected to the
E&M interface of the PABX.
Check the connection cables.
2. Problem at local
DV-MUX3
Activate tone injection at the remote DV-MUX3,
and check that the test tone is heard.
Deactivate tone injection, activate the voice
channel loop, and check that a strong sidetone is
heard in the telephone set earpiece. If not,
replace the local DV-MUX3 (fault on main board,
or on interface board, is suspected)
3. Problem at remote
DV-MUX3
Repeat the procedure given above for the
remote DV-MUX3.
8 TEST off
SYNC LOSS off
The local data channel
user does not receive
data.
Voice channel operates
normally
1. Problem on the
cables, or on the line
between the DTE and
DV-MUX3
Activate the data channel loopback and BERT
test.
If the RD/ERR indicator of the local DV-MUX3
does not light (no errors), check the cables and
the line between the DV-MUX3 and the DTE.
2. Problem at Local
DV-MUX3
If the RD/ERR indicator of the local DV-MUX3
lights during the above test, replace the local
DV-MUX3
3. Problem at the
remote DV-MUX3
Repeat the procedure given above for the
remote DV-MUX3
Table 4-1. Troubleshooting Chart (Cont’d)
CHAPTER 4 - DIAGNOSTICS
4-6 DV-MUX3 Installation and Operation Manual