Display Troubleshooting
26
Module Diagnostics
Modules are equipped with a status indicator LED
that can help troubleshoot possible issues. Under
normal operation, the status indicator LED should
flash once every 4 seconds.
Module Self-Test
If a module is blank, but has power supplied to it,
perform a module self-test to diagnose a module
or signal cable failure. To perform a self-test, follow
the steps below.
1�
Attach a signal cable to Port A and Port B on
the module. Refer to
2�
Disconnect the power to the module for 10 seconds.
3�
Reconnect the power to start the self-test.
4�
Verify the module is running a self-test.
Remove the signal cable and unplug power to the module for 10 seconds to stop the
self-test.
Troubleshooting
Note:
Disconnect power when servicing the display. Only qualified service personnel
should service internal electronic components.
Module and LED Problems
One or more LEDs are not lighting
•
Check/replace the signal cables on the module.
• If that does not help, the module may need to be replaced.
One or more LEDs on a single module will not turn off
•
Check/replace the signal cables on the module.
• If that does not help, the module may need to be replaced.
A section of the display is not working
•
Check/replace signal cables from the last working module in the row to the first non-
working module next to it.
• Check the back of the modules to see that the power LEDs are on.
• Make sure the power cable to the module is connected.
•
Move or replace the first non-working module with the one on the left of the non-
working section.
•
Move or replace the first module to the left of the non-working modules.
One row of modules is not working or shows a distorted message
•
Check/replace the signal cables to and from the first non-working module.
• Check for bent pins on the jack going to a non-working module.
Figure 19:
Module Self-Test
