Daktronics AB-1600-1.5,2.5 - Manual (Page 72)

Maintenance & Troubleshooting 4-28
4.19 Troubleshooting Checklist – Line Receiver Displays
If the display has a line receiver, the following table covers a few problems that might be encountered
while operating the display, along with a cause/remedy. While this list does not cover every possible
problem, it does list those that are most likely to occur.
Problem Possible Cause/Solution
One or more lamps will not light. • Replace the lamp.
• Replace the socket.
• Replace the lampbank.
One or more lamps will not turn off. • Check for metallic foreign objects on the lampbank
causing a short.
• Replace the lampbank.
Not all of one row of modules or part
of one row of modules is working. • Check for a bad vertical shift board (VSB) by
swapping in a known good vertical shift board.
• Replace the ribbon cable from the VSB to the
underlying lampbank.
• Check appropriate breaker in panelboard.
• Check for 230 VAC incoming display power.
• Replace the last working lampbank in that row.
Garbled display or shifted
sequence. • Set computer and line receiver to high line feed.
• Double check line receiver is set for correct display
size.
• Replace line receiver.
Group of 2 modules does not work. • Check appropriate breaker in panelboard.
• Check transformer for correct output (24 VAC).
Entire display does not work • Check for 230 VAC incoming display power.
• Check fuse in fan control enclosure.
• Check line receiver indicator LEDs.
• Check all signal connections.
Single module does not work • Check signal connection.
• Check power connections.
• Check appropriate breaker in panelboard.
• Replace lampbank.
Display works for a short time and
then blanks. • Check that all fans are operational and running at
full RPM.
• Check that filters are not plugged and limiting
airflow.