Troubleshooting Co Lines - NEC Aspire S Manual

Troubleshooting CO Lines

Is the Live
Status LED on
the COIU PCB
flashing green?
Is the Run/Block
switch (SW2) set
to block?
Yes
Set the Run/Block
switch to the Run
position.
Screen the problem
(whether problem
exists in system or
with central office).
Connect a test
telephone to the
CO line side. Is
dial tone heard?
Measure the loop
current on the line with
a digital voltmeter.
Verify if the problem is
with the main equipment
or the CO line by using a
test set before the
connection to the system.
Is the wiring for the
cables correct?
Check system
programming for the
extension. Refer to the
Aspire Software
Manual if necessary.
Aspire S Hardware Manual
Section 3: Installing Extensions and Trunks
Verify the COIU PCB
No
Yes
Can a call be placed
Yes
Is the PBXG grounding wire from
the PCB attached to the PBXG bar
in the cabinet and is there a proper
earth ground for the system?
Yes
Redo the wires between
the main equipment and
No
Yes
Try placing a call on the
CO line. Does it work?
The COIU PCB may
Start
is functioning.
No
No
Is the Live
Status LED on
No
the COIU PCB
flashing green?
Yes
on the CO line?
Yes
Contact the CO to
Stop
No
investigate the line.
* If it still does not work,
replace the cable(s) and/
the CO line.
No
need repair.
Section 3: Installing Extensions and Trunks ◆ 3-21
Main equipment
(cabinet/CPU) may
need repair.
No
Remove the PCB and
insert another COIU
PCB into the same
slot. Does it work?
Yes
The COIU PCB may
need repair.
Connect the proper
grounding wires for
No
the system.
or connectors.
Stop
Yes
3