Daktronics GPR-12EV-RGB - Manual (Page 37)

Diagnostics and Troubleshooting 31
One or more LEDs on a single module will not turn off
• Check/replace ribbon cables on the module.
• If that does not help, the module may need to be replaced.
A section of the display is not working, shown in Figure 32
• Check/replace ribbon cables from the last working module in the row to the first
non-
working
module
next to it.
• Move or
replace the
first non-
working
module,
the one on
the far left
of the non-
working
section.
• Move or
replace the
first module to the left of the non-working modules.
• Check the back of the modules to see that the power LEDs are on.
• Make sure the power cable to the module is connected.
One row of modules is not working or shows a distorted message
• Check/replace the ribbon cables to and from the first non-working module.
• Check for bent pins on the jack going to a non-working module.
• Move or replace the modules that show distorted text.
• Move or replace the first module to the left of the one that is not working.
• Check the fuse from the output and replace if necessary.
A column of the display does not work
• Check that the ribbon and power cables are plugged into the first module in the row.
• While power is on, look at the back of the first malfunctioning module to see if the
diagnostic LED is off, implying a power supply problem.
Entire display fails to work
• Check the breakers in the building connected to main power source.
• Check the breakers in the power termination panel (bottom row, second module
from the left).
• Check the fiber cables between the controller and the MLC.
• Check the diagnostic LEDs on the controller for Power and Run (Section 7.1).
• Check/replace the ribbon cable from the MLC to the modules.
Figure 32: Modules Not Working