IBM Application System/400 Service Information page 107

11
To continue problem analysis, use a port
tester, part 94X2040 or 59X4262, which
you may have with your tools. Your port
tester has either two or three lights.
Do you have a port tester available and a
display cable with a barrel or twisted pair
connector?
Yes No
~
Go to step 10 of this procedure.
12
DANGER
To prevent a possible electrical
shock, do not use the port tester
during electrical storms.
(RSFTD006)
To use the port tester to isolate the
problem, perform the following:
• Verify that the port tester is operating
correctly by doing a self-test. A self-
test can be made at any time, even
when the port tester is attached to a
port or cable. The self-test informs you
if the port tester is ready to be used.
Perform the following steps to do a
self-test:
a. Move the selector switch to the
center (0) position.
b. Push and hold the test pushbutton
until all lights come on. The yellow
lights should come on immediately,
and the green light should come on
approximately 5 seconds later. The
port tester is ready for use if all
lights come on.
• Leave the system power on.
• Connect the port tester to only one port
or cable.
13
Find the input cable to the failing console
and perform the following:
a. Disconnect the input cable from the
failing console.
b. Connect the port tester to the input
cable.
1 4
Set the selector switch on the port tester to
the left (1) pOSition for a twinaxial con-
nection and to the right (2) position for a
twisted pair connection.
Press and hold the test switch on the port
tester for 15 seconds and observe the
lights.
If your port tester has three lights, do
the following:
• If only the top (green) light is on, go to
step 20 of this procedure.
• If both the top (green) and center
(yellow) lights are on, go to step 16 of
this procedure.
Note: The center (yellow) light is
always on for twisted pair cable and
may be on for fiber optical cable.
• If only the bottom (yellow) light is on,
go to step 17 of this procedure.
• If all lights are off, go to step 18 of this
procedure.
• If all lights are on, go to step 15 of this
procedure.
If your port tester has two lights, do the
following:
• If only the top (green) light is on, go to
step 20 of this procedure.
• If only the bottom (yellow) light is on,
go to step 17 of this procedure.
• If both lights are off, go to step 18 of
this procedure.
• If both lights are on, continue with step
15 of this procedure.
15
The tester is in the self-test mode. Check
the position of the selector switch.
If the selector switch is not in the correct
position, go to step 14 of this procedure.
If the selector switch is already in the
correct position, the port tester is not
working correctly. Exchange the port tester
and go to step 12 of this procedure.
16
The cable you are testing has an open
shield.
Note: The open shield can be checked
only on the cable from the twinaxial work-
station attachment to the device or from
device to device. Only one section of cable
can be checked at a time. See the
Chapter 3. Problem Isolation Procedures
3-17