Daktronics CH-1421V - Manual (Page 18)

Maintenance & Troubleshooting 3-2
3.3 Digit Segmentation
Reference Drawing: Segments, 4x7 Lamp Matrix Digit.................. Drawing A-37685
In a digit certain lamps always go on and off together. These groupings of lamps are known
as “segments”. Each digit has eight segments, referred to by letters A through H. Drawing
A-37685 illustrates these segments and shows which connector pin and wire color is wired to
each segment.
3.4 Schematic
Reference Drawings: Schematic, 1 Driver Display ........................ Drawing A-38788
Pwr/Sig Entrance, 1 Driver Display ............. Drawing A-46755
Component Numbering,CH-1421V ........... Drawing A-106020
The schematic diagram in Drawing A-38788 shows the power and signal inputs into the
display and to the lamp driver. The component numbers correspond to those shown on
Drawings A-106020 and A-46755.
3.5 Troubleshooting
This section lists some symptoms that may be encountered with the CH-1421V display. For
these symptoms, possible causes and corrective actions are indicated. This list does not
include every possible problem, but does represent some of the more common situations that
may occur.
Observed Problem Possible Cause
One lamp won’t light
• Burned-out lamp
• Broken wire behind digit
Digit segment won’t light
• Broken wire
• Poor contact at driver connector
• Internal driver malfunction
Entire digit won’t light • Broken wire (black)
• Poor contact at connector, pin 7
• Fuse blown in driver
Half the display won’t light • Service breaker tripped
• Main fuse blown
• Poor contact at main power connection
• P18 disconnected
Entire display won’t light • Power disruptions
• Poor signal connection
• Driver logic fuse blown
• Control not connected to display
• P20 disconnected
Segment stays lit • Broken wire behind digit
• Internal driver malfunction
Garbled display • Control malfunction
• Internal driver malfunction