Daktronics VF-24 Series User manual

201 Daktronics Drive
Brookings, SD 57006-5128
www.daktronics.com/support
800.325.8766
GENERIC SERVICE
VF-24XX
DISPLAY MANUAL
8 January 2018
DD3811006
Rev 0

Copyright © 2018
All rights reserved. While every precaution has been taken in the preparation of this manual, the publisher assumes no
responsibility for errors or omissions. No part of this book covered by the copyrights hereon may be reproduced or copied
in any form or by any means—graphic, electronic, or mechanical, including photocopying, taping, or information
storage and retrieval systems—without written permission of the publisher.
Daktronics trademarks are property of Daktronics, Inc. All other trademarks are property of their respective companies.

– i –
Table of Contents
1 Introduction.........................................1
How to Use This Manual ............................1
Theory of Operation ..................................1
Vanguard®Software...............................1
VFC-3000 Controller/Vanguard®Field
Controller.................................................1
2 Components .......................................2
Modules ......................................................2
Power Supplies ...........................................2
Power Supplies .......................................2
Isolation Board........................................2
Vanguard®Control Board......................2
Surge Suppressor ....................................3
Relays ......................................................3
Ventilation and Heater Systems...............3
Intake Fans and Filters ...........................3
Defog Heater Fans..................................3
Beacon(s) ...................................................3
3 Maintenance and Troubleshooting ..4
Getting Started ........................................4
Service and Diagnostics ...........................4
Module Numbering System ......................4
7-Segment Error Codes .............................5
Modules...................................................5
VCB ..........................................................5
Isolation Board........................................5
VCB ..........................................................6
Modules...................................................7
Isolation Board........................................7
VFC-3000 Controller/Vanguard®Field
Controller Replacement...........................7
46/66mm Module Replacement .............8
20mm Module Replacement...................8
Environmental Sensors...............................9
Airow Sensor..........................................9
Light/Temperature/Humidity Sensor.....9
Power Supply Assembly Replacement ...9
Vanguard®Control Board (VCB) ...........10
Ventilation Fan and Filter Maintenance ...
...................................................................10
Filter Replacement ...............................10
Fan Replacement.................................10
Trafc Cabinet Maintenance.................11
Trafc Cabinet Fan and Thermostat
Assembly Replacement ......................11
Trafc Cabinet Light Replacement .....11
Display Maintenance..............................11
Structure ................................................11
Earth Ground Resistance .....................11
Display Cabinet ....................................11
Temperature and Light Sensors...........12
Ventilation Fans ....................................12
Filters ......................................................12
VFC-3000 Controller/Vanguard®Field
Controller...............................................12
Face Panels...........................................12
Wet Outdoor Cleaning Method..........12
Pressure Wash Cleaning Method........13
LED and Electronic Circuitry ................13
Maintenance Checklist ..........................14
Troubleshooting .......................................15
4 Replacement Parts and Exchange
and Repair Programs........................18
Daktronics Part Numbers ........................18
Daktronics Exchange and Repair &
Return Programs ......................................18
Exchange Program ..............................18
Before Contacting Daktronics.............18
Repair & Return Program .....................19
Shipping Address..................................20
Email ......................................................20

– ii –
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– 1 –
1 Introduction
How to Use This Manual
This manual explains the maintenance and troubleshooting of VF-24X0 series Dynamic
Message Signs (DMS). For information regarding the safety, installation, operation, or
service of this system, refer to the telephone numbers on the cover page of this manual.
Daktronics identies manuals by the ED or DD number located on the cover page of
each manual. For example, this manual is referred to as DD3811006.
The serial and model numbers for the display are on the ID label attached to the display.
This label looks similar to Figure 1. When calling Daktronics Customer Service, please have
this information available to ensure timely response.
Refer to the Daktronics Exchange and Repair & Return Programs (p. 18) if any
component needs replacement or repair.
Theory of Operation
Vanguard®Software
Daktronics Vanguard®software allows the DMS operator to check display status and to
control messages. Refer to the Vanguard®Software Help File [F1] for information about
operating Vanguard®software.
VFC-3000 Controller/Vanguard®Field Controller
The VFC-3000 controller/Vanguard®Field Controller is the communication hub for DMS
management; it may be located in the display or the trafc cabinet.
The central controller creates messages and transmits them to the VFC-3000 controller/
Vanguard®Field Controller for storage. Upon request from the central controller or the
front panel interface, the VFC-3000 controller/Vanguard®Field Controller locates the
message to display and sends it to the display’s modules via the Vanguard®control
board. The modules activate the appropriate pixels to form the message.
The VFC-3000 controller/Vanguard®Field Controller also monitors local sensors (display-
based sensors) like temperature, light level, and door detection. The VFC-3000 controller/
Vanguard®Field Controller interprets sensor data for display control and diagnostic
functions, such as adjusting the display’s intensity for current lighting conditions.
Refer to the controller manual for conguration information.
Figure 1: Display ID Label

– 2 –
2 Components
Modules
A module is a replaceable unit
consisting of a display panel with
clusters of LEDs, called pixels. The pixels
display messages on the display. Refer
to Figure 2 and Figure 3.
Each module contains drive electronics
that receive data packets from the
Vanguard®control board and lights
the appropriate pixels at the correct
dimming level.
Power Supplies
Power Supplies
The power supplies provide voltage to power the modules. Multiple
power supplies provide power redundancy. If one power supply in
the group fails, the other supports the full power load, preventing
power failure to the modules. Power supplies are mounted to panels
on the rear wall of the display.
Isolation Board
One isolation board mounts to each power supply. The isolation
board provides input and output voltage to the power supply.
Figure 4 shows an isolation board. The isolation board receives 120
VAC input voltage from the distribution panel. Output from the power
supply routes through the isolation board. From there, the 24 VDC
output routes to the DC breaker rail.
Isolation board diagnostics include power supply data sent to the
VFC-3000 controller/Vanguard®Field Controller about output voltage.
Vanguard®Control Board
The Vanguard®control board (VCB) receives high-speed serial data
from the VFC-3000 controller/Vanguard®Field Controller through
a ber-optic or Cat-5 cable. It then distributes the signal to the
appropriate modules and sensors. The VCB receives diagnostic data
from the modules, temperature and light sensors, and isolation boards
and transmits the data to the VFC-3000 controller/Vanguard®Field
Controller. The VCB uses an I/O interface to control beacons. The VCB
also monitors door sensors, ventilation fans, defog heaters, and power
supplies.
The VCB uses a protocol that routes signal to each horizontal line of
the display. With this protocol, signal failure to one module in a horizontal line does not
affect other LED modules in that line.
Figure 2: 20 mm Module (Rear
View) Figure 3: 34/66 mm
Module (Rear View)
Figure 4: Isolation
Board

– 3 –
Surge Suppressor
The parallel surge suppressor protects the display from transient voltage spikes.
Relays
Relays are solid-state switches in which the electrical current applied across one port or
terminal controls electrical currents for another terminal, such as a beacon, heater, or
fan. Relays receive signal from the VCB.
Ventilation and Heater Systems
Intake Fans and Filters
Filtered intake fans mount to the lower rear of the display. The VFC-3000 controller/
Vanguard®Field Controller analyzes temperature readings from the temperature sensor
network and adjusts fan usage. Additionally, an internal thermostat activates the fans
if the internal temperature exceeds a set limit. A lter removes dust and debris from the
incoming air to protect the internal display components.
Defog Heater Fans
If equipped, the heater fans mount to the bottom of the display. The heater fans warm
the front face to prevent fogging. The controller analyzes internal temperature readings
from the temperature sensor network and adjusts heater fan usage accordingly.
Beacon(s)
Beacons are turned on and off independently from the rest of the sign by the VCB.
Beacons are at the customer’s discretion.

– 4 –
3 Maintenance and Troubleshooting
Getting Started
1. Before performing any repair or maintenance to the displays:
a. Disconnect utility power.
b. Disable the display UPS system (if equipped) by shutting off the two switches on
the UPS head unit face panel.
2. Only qualied service personnel should access internal display electronics. Contact
Daktronics Customer Service for training needs.
3. Daktronics engineering staff must approve changes made to the displays. If making
modications, submit detailed drawings to the Daktronics engineering staff for
evaluation and approval or the warranty will be void.
Service and Diagnostics
The VF-24X0 series DMS are front accessible — all internal components are accessible
from within the display.
The following tools are required to service the display:
• Hex-head wrench (5/16")
• Stubby Phillips screwdriver
• Small Phillips screwdriver
• Small at-head screwdriver
• Small pliers
• Medium Phillips screwdriver
• Medium at-head screwdriver
• Nut driver (3/8")
• Cable ties
• Multimeter
• Clamp-on ground meter
Module Numbering System
Daktronics uses a module numbering system
to help with troubleshooting; refer to Figure 5.
Figure 5: Module Numbering

– 5 –
7-Segment Error Codes
A 7-segment indicator appears on the following components;
refer to Figure 6. The 7-segment indicator provides codes to
indicate any present errors and their cause. When an error
occurs, the 7-segment will ash the error code. If multiple errors
are present, the 7-segment will ash the errors individually in
succession. If no errors are present, the 7-segment will show a
continuously looping gure-8.
Modules
7-Segment Error Code Error Cause
1 Communications Lost No CAN packets received for
10 seconds
2 Failed Pixel Refer to the Troubleshooting
table.
3 Power Failure Input Voltage has dropped
below 20 VDC
8 (Solid) Lost Packet Diagnostic packet, FIFO full
8 (Looping) No Error
VCB
7- Segment Error Code Error Cause
1 Communications Lost No ber packets for 15
seconds
3 Power Failure
Board voltages below limit:
V-ln, 1 and 2 < 20 VDC
9 V < 8.52 VDC
3.3 V < 3 VDC
2.5 V < 2.37 VDC
1.2 V < 1.1 VDC
8 (Looping) No error
Isolation Board
7-Segment Error Code Error Cause
1 Communications Lost No CAN packets for 10
seconds
2 Input power failure V-In < 21 VDC
5 Output power failure V-In < 21 VDC (with V-ln OK)
8 (Looping) No Error
Figure 6: 7-Segment

– 6 –
Three 7-segment indicators appear on the
following component; refer to Figure 7. The
7-segment indicators provide codes to indicate
normal running conditions as well as any present
errors and their cause. When an error occurs, the
7-segment will ash the error codes individually in
succession. If no errors are present, the 7-segment
will continuously cycle normal running conditions.
VCB
7- Segment Error Code Error Cause
E r r Error
If an error condition exists, the
VCB will display E r r then the
remaining error codes.
i d Hardware ID
Hardware ID (jumpers on
the module) can’t be read
correctly (parity error), or
have changed during runtime
A d r Address ProLink 6 address does not
match rotary switch setting
h r d Hardware
-Errors on PL6 link(s)
-Error on sensor CAN port
On board voltage error
(measurement out of range)
-Invalid or high VCB
temperature reading
-Error reading / writing to serial
FLASH
-Error with EPLD
-7-segment display errors
(bad segment)
-Input voltage out of range
c o d Firmware
-Invalid interrupt occurred
-Micro bootloader FW not
found
-Stack overow
-EEPROM write / erase error
-No EPLD bootloader
program found, or running
EPLD bootload FW when it
shouldn’t be
-Invalid PL6 modify packet
P L 6 ProLink 6 Port A and Port B not in sync
Figure 7: Three 7-Segment Indicators

– 7 –
A single 7-segment indicator appears on the following components; refer to Figure 8. The
7-segment indicator provides codes to indicate any present errors and their cause. When
an error occurs, the 7-segment will ash the error code. If multiple errors are present,
the 7-segment will ash the errors individually in succession. If no errors are present, the
7-segment will show a continuously looping gure-8.
Modules
7-Segment Error Code Error Cause
1 Communications Lost No CAN packets received for
10 seconds
2 Failed Pixel Refer to the Troubleshooting
table.
3 Power Failure Input Voltage has dropped
below 20 VDC
8 Lost Packet Diagnostic packet, FIFO full
8 (looping) No Error
Isolation Board
7-Segment Error Code Error Cause
1 Communications Lost No CAN packets for 10
seconds
2 Input power failure V-In < 21 VDC
5 Output power failure V-In < 21 VDC (with V-ln OK)
8 (looping) No Error
VFC-3000 Controller/Vanguard®Field Controller
Replacement
1. Turn off the power switch on the VFC-3000 Controller/Vanguard®Field
Controller face.
2. Label and remove all of the connections from the front and rear of the
VFC-3000 controller/Vanguard®Field Controller.
3. Remove the screws securing the VFC-3000 controller/Vanguard®Field
Controller to the inside of the display or the trafc cabinet and remove
the controller.
4. Perform the needed maintenance.
5. When the VFC-3000 controller/Vanguard®Field Controller is ready for
installation, slide it back into place.
6. Hold the controller in place and install the mounting screws.
7. Reconnect all connectors removed from the VFC-3000 controller/Vanguard®Field
Controller.
8. Secure any retaining screws and prepare the VFC-3000 controller/Vanguard®Field
Controller for operation.
Figure 8:
7-Segment

– 8 –
Module Replacement (46/66mm)
1. Turn off power to the failed module by turning off the breakers for all power supplies.
2. Remove the wire connections:
a. Press the locking tabs of the 2-pin power connector and remove the connector.
b. Press the tabs of the 8-pin signal connector and remove the connector.
3. Carefully unlatch the 10 locking tabs holding the module in place.
4. Remove the module from the display face.
5. Align the new module with the 10 tabs and carefully snap it into place, ensuring each
tab is secure.
6. Plug the 2-pin power connector and 8-pin signal connector into the new module.
Note: The connectors only t together one way; do not force the connection.
8. Reapply power to the power supplies turned off in Step 1.
9. Test the modules:
a. Display the moving row, moving column, and all on/all off test messages. Run
the test messages at both 10% and 100% brightness settings. Watch for proper
operation of the LED module during each test message.
b. Perform a pixel test and check that all pixels operate correctly.
Module Replacement (20mm)
1. Turn off power to the failed module by turning off the breakers for all power supplies.
2. Remove the wire connections:
a. Press the locking tabs of the 2-pin power connector and remove the connector.
b. Press the tabs of the 8-pin signal connector and remove the connector.
3. Unlatch the 9 plastic wingnuts securing the module to the display.
4. Remove the module from the display face.
5. Align the new module with the 9 studs and replace the wingnuts.
6. Replace the 9 plastic wingnuts removed in Step 3.
7. Plug the 2-pin power connector and 8-pin signal connector into the new module.
Caution: Modules are not hot swap components. Always turn off power to the
modules prior to servicing.
Note: If a wingnut is lost, replace it with only plastic wingnuts. Do not use metal
wingnuts.
Note: The connectors only t together one way; do not force the connection.

– 9 –
8. Reapply power to the power supplies turned off in Step 1.
9. Test the modules:
a. Display the moving row, moving column, and all on/all off test messages. Run
the test messages at both 10% and 100% brightness settings. Watch for proper
operation of the LED module during each test message.
b. Perform a pixel test and check that all pixels operate correctly.
Environmental Sensors
Airow Sensor
To remove the sensor:
1. Locate the failed sensor reported by the controller.
2. Turn off the intake fan breaker.
3. Loosen the 1/4-turn fasteners in the upper corners of the intake fan assembly panel
and rotate the intake assembly forward.
4. Disconnect the Mate-n-Lok®connector.
5. Remove the nut and mechanical screw holding the sensor in place.
To replace the sensor, repeat the above steps in reverse order.
Light/Temperature/Humidity Sensor
To remove the sensor:
1. Locate the failed sensor reported by the controller.
2. Disconnect the terminal block from the sensor.
3. Remove the two Phillips screws fastening the sensor to the mounting plate.
4. Ensure the address of the sensor is the same as the address of the sensor being
replaced.
To replace the sensor, repeat the above steps in reverse order.
Power Supply Assembly Replacement
Power supply assemblies are mounted on the rear interior of the display.
1. Turn off power to the power supply assembly by turning off the breaker in the
distribution panel.
2. Locate the failed power supply assembly reported by the VFC-3000 controller/
Vanguard®Field Controller.
3. Loosen the screws securing the power supply assembly to the backsheet, and gently
lift the power supply assembly off the backsheet.
4. Ensure the power supply is addressed the same as the power supply being replaced.
To replace the new power supply, repeat the above steps in reverse order.

– 10 –
Vanguard®Control Board (VCB)
To replace the VCB (PC1):
1. Turn off the circuit breakers powering all power supplies.
2. Remove all connections to the VCB, including incoming signal from the VFC-3000
controller/Vanguard®Field Controller and outgoing signal to the modules and
sensors.
3. Remove the screws holding the board in place, and carefully remove the failed VCB.
4. Position the new board in the enclosure and secure with the screws removed in
Step 3. Securely fasten the screws to ensure proper grounding.
5. Reconnect all connections removed in Step 2.
6. Match the address of the new VCB to the address of the VCB being replaced.
7. Restore power.
Ventilation Fan and Filter Maintenance
Each time an intake fan assembly is opened, perform the following:
• Check the fan blades for dirt and debris. Clean the fan blades to maintain the
fan’s efciency and to ensure proper cooling. If the fan blades have a large
accumulation of dirt and debris, change the lters more often.
• Spin the fan blades with a pen or pencil to ensure the bearings are free and the
fan is balanced.
• Check the lters every year. Clean the lters with water and a mild detergent,
such as dish soap.
• Compressed air can be used to clean the lter provided the nozzle is held at
least 6" away from the lter, the pressure is no greater than 60 psi, and the air is
blown through the lter opposite the airow direction as indicated by the arrow
stamped on the lter frame.
Filter Replacement
1. Turn off the intake fan breaker.
2. Loosen the 1/4-turn fasteners in the upper corners of the intake fan assembly panel.
3. Rotate the intake assembly forward and slide the lter out.
4. Slide a new lter into the panel. Ensure the lter is oriented in the same position as the
lter being replaced.
5. Rotate the fan assembly back into its original position and tighten the 1/4-turn
fasteners.
Fan Replacement
1. Unplug the fan cord and cut the cable ties.
2. Remove the hardware holding the fan and nger guard in place.
3. Remove the failed ventilation fan.
To replace the ventilation intake fan, follow the previous steps in reverse order. Ensure the
fan is properly oriented.

– 11 –
Trafc Cabinet Maintenance
Trafc Cabinet Fan and Thermostat Assembly Replacement
1. Open the panelboard and turn off the circuit breaker supplying power to the fan and
thermostat assembly.
2. Disconnect the fan’s power cord.
3. Remove the hardware securing the nger guard and fan to the assembly bracket
and remove the fan.
4. Attach the new fan to the bracket and secure it using the hardware removed in Step
3. Note the airow orientation when attaching the new fan.
5. Reconnect power to the fan.
6. Adjust the thermostat to test the fan.
Trafc Cabinet Light Replacement
1. Turn off the circuit breaker that powers the light.
2. Remove the lamp cover and lamp.
3. Insert a new lamp into the assembly and replace the cover.
4. Restore power and test the light.
Display Maintenance
The following service intervals are recommendations.
Structure
At least once per year:
• Inspect the mounting structure for corrosion, loose bolts, and overall stability.
• Check the connections of the earth ground wires, if accessible.
Earth Ground Resistance
At least once per year ensure earth ground resistance measures 10 ohms or less at the
site. An earth ground can run from the ground lug on the outside of the cabinet to
an earth-ground rod(s). Ensure the ground is measured as close to the ground rod as
possible.
Note: Ground meters for this test are available for purchase from Daktronics.
Display Cabinet
At least once per year:
• Check for water stains and other signs of water intrusion in the display cabinet.
• Seal any leaks that have developed with a silicone sealant or another suitable
sealer.
• Repair any door gaskets that have tears or missing pieces.
• Check the drainage holes in the bottom of the cabinet for obstructions.

– 12 –
Temperature and Light Sensors
At least once per year:
• Clear away any obstructions to airow around the temperature and light sensors.
• Clean the windows if they are dirty.
Ventilation Fans
At least once per year:
• Verify all fans work by pushing the test button until the fans turn on.
• Open the intake fan assembly and clean any dirt and debris off the fan blades.
Spin the fan blades with a pen or pencil to ensure the bearings are free and the
fan is balanced.
Filters
Check and clean the lters at least once per year. If the lter has an excess of dirt and
dust, check the lters more frequently.
VFC-3000 Controller/Vanguard®Field Controller
At least once per year:
• Ensure all connectors are secure and the cables are not damaged in any way.
• Check the VFC-3000 Controller/Vanguard®Field Controller operation.
Face Panels
Clean the face panels as needed, using one of the following methods.
Wet Outdoor Cleaning Method
Cleaning supplies:
• Water
• 5-gal bucket
• Automotive detergent
• Telescoping, soft automotive brush with bristles that are light to medium in rigidity
• Several soft terry cloth towels
Cleaning process:
1. Turn off power to the DMS.
2. Mix the automotive detergent and cold water in the 5-gal bucket at 1 oz detergent
to 1 gal of cold water. Distilled water is preferred, but not required.
3. Dip the brush in the bucket of soapy water.
4. Using brush strokes, wash the display from top to bottom.
Note: Using a soap-dispensing brush with a low soap-to-water ratio eliminates
excess soap residue.
5. Thoroughly rinse the display face with cold water under low pressure.
6. Use a soft, dry terry cloth to dry and remove any excess water.

– 13 –
Pressure Wash Cleaning Method
Cleaning supplies:
• Pressure washer rated for 1,500 psi or less
• 45° (or more) spray nozzle
Cleaning process:
1. Turn off power to the DMS.
2. Spray face and sides of the DMS. Keep the nozzle of the pressure washer at least 2'
away from the display.
Note: Use caution along areas of the display that contain seams, weather stripping, or
silicone. Ensure the pressure washer does not peel or rip any sealing material.
LED and Electronic Circuitry
Test LED and electronic circuitry at intervals determined by customer requirements.
Daktronics recommends performing the tests at least monthly. Perform tests on the DMS
to check for hardware problems and incorrect variable settings.
Note: The following tests display functions, not other DMS equipment hardware.
1. Connect to the VFC-3000 controller/Vanguard®Field Controller and establish
communication with the display.
2. Check that the temperature levels shown on the Sign Status screen of the Sign
Control tab are the appropriate values for both internal and external temperature.
3. Perform a diagnostics test and check that all the power supplies and other
congured peripherals pass.
4. Make sure the photocell readings are appropriate for the current conditions.
5. Perform a pixel test and replace faulty modules.

– 14 –
Maintenance Checklist
Refer to the instructions in the Display Maintenance (p. 11) section. One copy of the
following service interval table may be lled out for each display.
Display Location:
Maintenance Item
Monthly
Remote
Diagnostics
1 yr. As
Needed Dates Performed and Initials
Secure Connections X
Earth Ground
Resistance X
Display Cabinet X
Structural Inspection X
Light/Temp Sensors X
Face Panels X
LEDs X
Ventilation Fans /
Filters X
Internal Hardware X
LED and Electronic
Circuitry X

– 15 –
Troubleshooting
For additional assistance, contact Daktronics Transportation Customer Service at the
telephone number on the cover page.
Problem Observed Possible Cause Solution
No LEDs light, and the VFC-
3000 controller/Vanguard®
Field Controller does not
communicate with the central
controller.
No power. Check that the trafc cabinet
has power.
VFC-3000 controller/Vanguard®
Field Controller or modem is
bad.
Refer to the appropriate
controller manual.
No LEDs light, but the VFC-
3000 controller/Vanguard®
Field Controller communicates
with the central controller.
All peripherals indicate
Communication Error.
No power at the display.
Check that the circuit breakers
in the trafc cabinet are on
and not tripped.
VFC-3000 controller/Vanguard®
Field Controller is bad or is not
connected to the display.
Refer to the appropriate
controller manual.
VCB is bad. Replace VCB.
No LEDs light, but the
peripherals pass and
the VFC-3000 controller/
Vanguard®Field Controller
is communicating with the
central controller.
VCB is bad. Replace VCB.
No power to power supply
groups.
Check that the circuit breakers
are on and are not tripped.
LEDs on the entire display are
garbled, or wrong LEDs are on
throughout the display.
Signal connections at the VCB
are incorrect. Check the signal wiring.
VFC-3000 controller/Vanguard®
Field Controller is bad.
Refer to the appropriate
controller manual.
VFC-3000 controller/Vanguard®
Field Controller has the wrong
display conguration.
Refer to the appropriate
controller manual.
One line of modules does not
respond properly. LEDs are
garbled, do not change, are
too bright or too dim, etc.
One or more wires or terminals
in the signal cable (for this
line) is misplaced, open or
shorted to wires or frame, in
display, VFC-3000 controller/
Vanguard®Field Controller, or
control cable from display to
Vanguard®Field Controller.
Repair wires as needed.
Terminating resistor on the CAN
bus for this line is bad.
Replace the terminating
resistor.
One or more drivers in this line
are bad.
Replace modules in the line
one at a time and retest each
time. Note: There may be more
than one bad driver. Repair
the failed driver.
VCB is bad. Replace VCB.

– 16 –
Problem Observed Possible Cause Solution
No LEDs on a module light.
Power connector unplugged
at module. Plug in connector.
Address and signal connector
unplugged at module. Plug in connector.
Power plug terminals are not
properly seated, or the wire is
bad.
Inspect all wires and terminals
for power plug. Repair as
needed.
The module is bad. Replace failed module.
One module is garbled, too
bright or too dim, erratic, etc.
Signal plug terminals are not
seated well at driver board, or
wire is bad.
Inspect all wires and terminals
for 8-pin plug. Repair as
needed.
The module is bad. Replace failed module.
One pixel does not turn off. The module is bad. Replace failed module.
One pixel does not light. The module is bad. Replace failed module.
One string (half the LEDs) in
one pixel does not light. The module is bad. Replace failed module.
Electronically controlled fans or
heaters are reported as on, but
all are off.
Circuit breaker tripped. Reset breaker.
Relay is bad. Replace relay.
VCB is bad. Replace failed VCB.
Ventilation fans do not run.
Circuit breaker tripped in trafc
cabinet. Reset the breaker.
Temperature inside the display
is lower than the thermostat
setting.
This is not a problem.
The thermostat or its wiring is
bad. Repair as needed.
VCB is bad. Replace failed VCB.
Ventilation fans run
continuously.
Temperature inside the display
exceeds the thermostat
setting.
This is not a problem.
The thermostat is stuck on or
the wiring is shorted.
Replace the thermostat or
repair wiring.
VCB is bad. Replace failed VCB.