Federal Signal Corporation CN SignalMaster Manual

25500013
REV. B1 0220
Printed in U.S.A.
© Copyright 2016-2020 Federal Signal Corporation
Installation, Maintenance,
and Service Manual
CN SignalMaster™

blank page
Limited Warranty
This product is subject to and covered by a limited warranty, a copy of which
can be found at www.fedsig.com/SSG-Warranty. A copy of this limited war-
ranty can also be obtained by written request to Federal Signal Corporation,
2645 Federal Signal Drive, University Park, IL 60484, email to
[email protected] or call [phone].
This limited warranty is in lieu of all other warranties, express or implied,
contractual or statutory, including, but not limited to the warranty of mer-
chantability, warranty of tness for a particular purpose and any warranty
against failure of its essential purpose.
2645 Federal Signal Drive
University Park, Illinois 60484-3167
www.fedsig.com
Customer Support
Police/Fire-EMS: 800-264-3578 • [phone]
Work Truck: 800-824-0254 • [phone]
Technical Support 800-433-9132 • [phone]

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Installation, Operation, and Service Manual
Federal Signal www.fedsig.com
Contents
Safety Messages for Installers and Service Personnel ............................................................... 4
Safety Messages for Operators of Warning Lights ...................................................................... 7
An Overview of the CN SignalMaster ............................................................................................ 8
LED Lights, Colors, and Flash Patterns......................................................................................................8
Installing the CN SignalMaster....................................................................................................... 9
Mounting the CN SignalMaster....................................................................................................................9
Wiring the CN SignalMaster in the Vehicle.............................................................................................10
Wiring the SignalMaster Function......................................................................................................... 11
Wiring the Light Bar Controls................................................................................................................. 11
Setting Configuration Options.................................................................................................................... 13
Testing the Light Bar ..................................................................................................................................... 14
Maintaining and Servicing the CN SignalMaster........................................................................ 15
Replacing a PCB............................................................................................................................................. 15
Replacing a Reflector.................................................................................................................................... 18
Getting Technical Support and Service....................................................................................... 19
Getting Repair Service.................................................................................................................................. 19
Ordering Replacement Parts ...................................................................................................................... 19
Figures
Figure 1 Mounting brackets attached to CN SignalMaster...................................................................... 10
Figure 2 DIP switches on the CN SignalMaster controller PCBA.......................................................... 14
Figure 3 Exploded front view of Model CNSM8 ........................................................................................ 15
Figure 4 Exploded rear view of Model CNSM8 ......................................................................................... 16
Figure 5 Exploded rear view of Model CNSM4 ......................................................................................... 17
Figure 6 Exploded rear view of Model CNSM2X4R ................................................................................. 17
Figure 7 Removing a reflector ........................................................................................................................ 18
Tables
Table 1 Mounting kit contents ...........................................................................................................................9
Table 2 CN SignalMaster controls and wires from the Serial Interface Module................................ 12
Table 3 CN SignalMaster DIP switch settings............................................................................................. 13
Table 4 Common replacement parts ............................................................................................................ 19

4CN SignalMaster™
Federal Signal www.fedsig.com
Safety Messages for Installers and Service Personnel
Safety Messages for Installers and Service Personnel
For your safety, read and understand this manual thoroughly before installing,
operating, and servicing the CN SignalMaster™. The safety messages presented in this
section and throughout the manual are reminders to exercise extreme care at all times.
Read and understand the safety instructions to installers (doc. no. 256A692), and keep
it close at hand for reference. To download copies of this manual, go to
www.fedsig.com or call the Federal Signal Service Department at 1-800-433-9132,
7a.m. to 5 p.m., Monday through Friday (CT).
People’s lives depend on your proper installation and servicing of Federal Signal
products. It is important to read and follow all instructions shipped with this product.
Listed below are some other important safety instructions and precautions you should
follow.
Before Installation or Service
Qualifications
• To properly install or service this equipment, you must have a good understanding
of automotive mechanical and electrical procedures and systems, along with
proficiency in the installation and service of safety warning equipment. Always
refer to the vehicle’s service manuals when performing equipment installations on
a vehicle.
Light Hazards
• To be an eective warning device, this product produces bright light that can be
hazardous to your eyesight when viewed at a close range. Do not stare directly
into this lighting product at a close range, or permanent damage to your eyesight
may occur.
• Do not install the light system in an area that would block, impair, or blind the
driver’s vision. Ensure that the light system is mounted in a position that is outside
the driver’s field of vision so the driver can safely operate the vehicle.
• Federal Signal power supplies and light heads are designed to work together as
a system. Combining light heads and a power supply from dierent manufacturers
may reduce the warning eectiveness of the lighting system and may damage the
components. You should verify or test your combination to ensure that the system
works together and meets federal, state, and local standards or guidelines.
Electrical Hazards
• The lighting system components, especially light bulbs, strobe tubes, LEDs, and
the outer housing, get hot during operation. Disconnect power to the system and
allow the system to cool before handling any components.
• A light system is a high current system. In order for the system to function
properly, a separate negative (–) connection and positive (+) connection must
be made. All negative connections should be connected to the negative battery

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Installation, Operation, and Service Manual
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Safety Messages for Installers and Service Personnel
terminal, and a suitable fuse should be installed on the positive battery terminal
connection as close to the battery as possible. Ensure that all wires and fuses are
rated to handle the device and system amperage requirements.
• Never attempt to install aftermarket equipment that connects to the vehicle
wiring without reviewing a vehicle wiring diagram available from the vehicle
manufacturer. Ensure that your installation will not aect vehicle operation or
mandated safety functions or circuits. Check the vehicle for proper operation after
installation.
• Do not mount a radio antenna within 18 inches (45.7 cm) of the lighting system.
Placing the antenna too close to the lighting system could cause the lighting
system to malfunction or be damaged by strong radio fields. Mounting the
antenna too close to the lighting system may also cause the radio noise emitted
from the lighting system to interfere with the reception of the radio transmitter and
reduce radio reception.
• Do not attempt to wash any unsealed electrical device while it is connected to its
power source.
During Installation and Service
• DO NOT get metal shavings inside the product. Metal shavings in the product
can cause the system to fail. If drilling must be done near the unit, place an ESD-
approved cover over the unit. Inspect the unit after mounting to be sure there are
no shavings present in or near the unit.
• DO NOT connect this system to the vehicle battery until ALL other electrical
connections are made, mounting of all components is complete, and you have
verified that no shorts exist. If the wiring is shorted to the vehicle body or frame,
high current conductors can cause hazardous sparks, resulting in electrical fires or
flying molten metal.
• DO NOT install equipment or route wiring (or the plug-in cord) in the deployment
path of an airbag.
• If a vehicle seat is temporarily removed, verify with the vehicle manufacturer if the
seat needs to be recalibrated for proper airbag deployment.
• Before mounting any components, check the manual to be sure that the
component you are installing is suitable for use in that area of the vehicle. Many
components are not suitable for use in the engine compartment or other extreme
environmental exposure areas.
• When drilling into a vehicle structure, ensure that both sides of the surface are
clear of anything that could be damaged. Remove all burrs from drilled holes. To
prevent electrical shorts, grommet all drilled holes through which wiring passes.
Ensure that the mounting screws do not cause electrical or mechanical damage to
the vehicle.
• Refer to the manual packed with the lighting system for proper electrical
connections, additional precautions,and information.

6CN SignalMaster™
Federal Signal www.fedsig.com
Safety Messages for Installers and Service Personnel
• Tighten adjustment bolts 10 ft-lb to 11 ft-lb to prevent the light bar from sliding
front-to-back when pulling on the mounting bracket. Install keeper plates.
• Locate the light system controls so the VEHICLE and CONTROLS can be operated
safely under all driving conditions.
After Installation or Service
• After installation, test the light system to ensure that it is operating properly.
• Test all vehicle functions, including horn operation, vehicle safety functions, and
vehicle light systems, to ensure proper operation. Ensure that the installation
has not aected the vehicle operation or changed any vehicle safety function or
circuit.
• Scratched or dull reflectors, mirrors, or lenses will reduce the eectiveness of
the lighting system. Avoid heavy pressure and use of caustic or petroleum-based
products when cleaning the lighting system. Replace any optical components that
may have been scratched or crazed during system installation.
• Do not attempt to activate or deactivate the light system control while driving in a
hazardous situation.
• Frequently inspect the light system to ensure that it is operating properly and that
it is securely attached to the vehicle.
• After installation and testing are complete, provide a copy of these instructions to
instructional sta and all operating personnel.
• File these instructions in a safe place and refer to them when maintaining and/or
reinstalling the product.
Failure to follow all safety precautions and instructions may result in property damage,
serious injury, or death.
RETAIN AND REFER TO THIS MESSAGE

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Safety Messages for Operators of Warning Lights
Safety Messages for Operators of Warning Lights
People’s lives depend on your safe use of our products. Listed below are some
important safety instructions and precautions you should follow.
• Do not attempt to activate or deactivate the light system control while driving in a
hazardous situation.
• Although your warning system is operating properly, it may not be completely
eective. People may not see or heed your warning signal. You must recognize
this fact and continue to drive cautiously.
• Situations may occur that obstruct your warning signal when natural and man-
made objects are between your vehicle and others, such as raising your hood or
trunk lid. If these situations occur, be especially careful.
• All eective sirens and horns produce loud sounds that may cause, in certain
situations, permanent hearing loss. You and your passengers should consider
taking appropriate safety precautions, such as wearing hearing protection.
• In order to be an eective warning device, this product produces bright light that
can be hazardous to your eyesight when viewed at a close range. Do not stare
directly into this lighting product at a close range, or permanent damage to your
eyesight may occur.
• It is important that you fully understand how to safely operate this warning system
before use.
• Operate your vehicle and its light/sound system in accordance with your
department’s Standard Operating Procedures.
• If a selected function does not perform properly or if any of the lamps remain
illuminated when the control is o, disconnect the power connector from the
control unit and contact the nearest service center.
• At the start of your shift, ensure that the entire warning light system and the siren
system are securely attached and operating properly.
Failure to follow these precautions may result in property damage, serious injury, or
death.
RETAIN AND REFER TO THIS MESSAGE

8CN SignalMaster™
Federal Signal www.fedsig.com
An Overview of the CN SignalMaster
An Overview of the CN SignalMaster
The CN SignalMaster™is a single-level LED light bar with ROC™(Reliable On-Board
Circuitry) and Solaris®LED technologies. ROC eliminates approximately 85 percent of
potential failure points by incorporating a printed circuit board (PCB) in one assembly
to substantially reduce the number of electrical connections. Solaris S2 LED modules
use oset, complex reflector surfaces for accurate beam shaping and the highest
optical eciency. The CN SignalMaster is available in eight-head and four-head
models for both front and rear. It is also available in a rear only, split eight-head model,
with a 12-foot cable joining two four-head units (CNSM2X4R).
LED Lights, Colors, and Flash Patterns
The light bar’s internal microprocessor supplies three priority operational modes
and a library of 27 flash patterns. To increase the safety of ocers, pedestrians, and
motorists, the light bar has standard dimming and intersection warning. Multi-color
heads are available with up to three dierent colored LEDs, eliminating the loss of
primary warning colors in takedown and directional warning positions. Individual
CN SignalMaster lightheads can flash between red, blue, amber, or white. The light
bar operates at a nominal input of 13.6 Vdc (11 Vdc minimum) and an operating
temperature range of –30°C to +65°C.
The functions of the SignalMaster are controlled through the CAT5 serial
communication cable. The cable connects to either a compatible Federal Signal
Serial control head or a Federal Signal Serial Interface Module (P/N 8583446). An
internal PCB assembly within the light bar decodes the control data and performs the
requested function. With the Serial Interface Module, the light bar can be activated by
Federal Signal light bar controllers, SignalMaster controllers, and/or individual low-
current switches.
The housing is an anodized aluminum extrusion. The light bar has 15-foot power and
ground cables and a 25-foot serial cable. Universal mounting hardware is supplied;
vehicle-specific mounting hardware is also available separately.

9
Installation, Operation, and Service Manual
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Installing the CN SignalMaster
Installing the CN SignalMaster
After unpacking the CN SignalMaster™, inspect it for damage that may have occurred
in transit. If it has been damaged, do not install it. File a claim immediately with the
carrier, stating the extent of damage. Carefully check all envelopes, shipping labels,
and tags before removing or destroying them. Ensure that the parts listed in Table 1
are included in the package. If you are missing any parts, contact Customer Support
at 1-800-264-3578, 7 a.m. to 5 p.m., Monday through Friday (CT).
An installer-supplied control head is also required for controlling the functions of the
light bar.
Table 1 Mounting kit contents
Qty. Description Part Number
2 Bracket, Mounting, SML 8652180
4 Screw, #10 Type B, Pan 6-Lobe, Blk SS 7011246-06
2 Nut,1/4-20 Keps®,SS 7058050
1 Grommet, Split 228128
NOTE: The CNSM2X4R includes two mounting kits.
Mounting the CN SignalMaster
LOCATING OPERATOR CONTROLS: The controls for the light system must be
located so that the VEHICLE and CONTROLS can be operated safely under all
driving conditions.
SIGNALMASTER ORIENTATION: The CN SignalMaster light bar must be
oriented correctly for proper operation. Install the assembly with the ROC
board on top.
IMPORTANT: Plan all cable routing before completing the installation. Plan the
location of the wire routing hole so that the cables do not have tight bends. For Model
CNSM2X4R, ensure that the board to board connection is in a dry interior location.
To mount the light bar:
1. Determine the appropriate spacing of the mounting holes for your application.
2. Install the mounting brackets to the CN SignalMaster with two #10 6-lobe screws
per bracket. See Figure 1 on page page 10.
3. Mark and drill two 17/64-inch holes for the mounting studs and a 3/4-inch hole for
the cables.
4. Install the grommet, route the cables, and then secure the light bar with the
1/4"-20 Keps nuts. Leave slack in the cables behind the panel to ease the removal
of the light bar.

10 CN SignalMaster™
Federal Signal www.fedsig.com
Installing the CN SignalMaster
Figure 1 Mounting brackets attached to CN SignalMaster
290A6967
SignalMaster
Aluminum Extrusion
Stud for 14"-20 Keps Nut
#10 Torx Screw (4)
Mounting Bracket (2)
Wiring the CN SignalMaster in the Vehicle
INSTALLATION PRECAUTIONS: The warning system and/or two-way radio
system may operate improperly if a two-way radio antenna is installed on or
within 18 inches of the light bar. Before permanently installing the light bar or
a two-way radio antenna, test the warning system and two-way radio system.
Some installations may require the relocation of the two-way radio antenna
to the trunk or fender. DO NOT drill holes in the light bar or install auxiliary
devices on the light bar, or the warning system may fail.
Before proceeding, ensure that the light bar has been installed inside the vehicle in
accordance with the instructions included with the mounting kit.
NOTE: The DIP switch on the light bar’s control PCB provides three selectable
options. To change DIP switch selections, refer to “Setting Configuration Options” on
page 13.
The CN SignalMaster™is completely wired at the factory and does not require any
additional internal wiring. Two 16AWG power conductors (red and black) and the
CAT5 communication cable exit the light bar. The conductors necessary to control the
light bar are contained in the CAT5 cable, which connects to a compatible Federal
Signal control head or to the Serial Interface Module.

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Installation, Operation, and Service Manual
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Installing the CN SignalMaster
EXPLOSION HAZARD: To avoid a battery explosion, always disconnect the
negative battery cable rst and reconnect it last. Avoid causing a spark when
connecting near or to the battery. The gases produced by a battery can cause
a battery explosion that could result in vehicle damage and serious injury.
SEAT REMOVAL PRECAUTION: If a vehicle seat is temporarily removed, verify
with the vehicle manufacturer if the seat needs to be recalibrated for proper
airbag deployment.
REVERSE POLARITY/MISWIRING: Reverse polarity may damage the light bar.
To avoid damage to the siren/amplier, ensure that the battery voltage is the
same voltage as the rating of the light and that the correct polarity is observed.
The light bar must be fused at the source.
To wire the light bar in the vehicle:
1. Ensure that the lines are adequately fused. From the light bar, route the CAT5
control cable into the vehicle’s cab or trunk near the planned location of a control
head that is compatible with the light bar or Serial Interface Module.
NOTE: An input cable (24-pin harness) is provided with the Serial Interface
Module. For connections, see document P/N 2562248.
2. Route and connect the 16 AWG black lead to the vehicle battery’s ground (–NEG)
terminal.
3. Route and connect the 16 AWG red lead through the user-supplied 15 A fuse at the
source to the positive (+BAT) terminal.
Wiring the SignalMaster Function
The SignalMaster directional warning function is configured at the factory and does
not require any additional wiring inside the light bar. All conductors necessary for
control of the SignalMaster are through the compatible serial communication control
head or the Serial Interface Module. For wiring and operation, refer to the instructions
included with the control head or document P/N 2562248 included with the Serial
Interface Module. The SignalMaster function is not available for front-facing models.
Wiring the Light Bar Controls
Both the Federal Signal serial control head and the Serial Interface Module provide
the controls in Table 2 to the light bar. The table shows the corresponding control
wires from the Serial Interface Module and their colors. The wire’s first color is the
predominant color and additional colors are stripes.

12 CN SignalMaster™
Federal Signal www.fedsig.com
Installing the CN SignalMaster
For programming options, see the instructions included with the Interface Module or
the Federal Signal serial control head.
Table 2 CN SignalMaster controls and wires from the Serial Interface Module
Light Bar Controls Wire Color Description
Mode 1 Blue Lowest priority
Mode 2 Blue/White Overrides Mode 1
Mode 3 Black/Red Overrides Modes 1 and 2
Steady Burn Red/White One (driver side) or two heads (driver and
passenger side) burn steadily when 12 Vdc is
applied to the control wire for Steady Burn. See
“Setting Conguration Options” on page 13.
Front Cutoff* Green/White Turns OFF power to the Front CN SignalMaster.
Rear Enable* Green/White Turns ON power to the Rear CN SignalMaster.
Not available for Front CN SignalMaster.
Flash Takedown Red/Black Flashes the Takedown lights in Modes 1, 2,
and 3 with every ash pattern. To have the
Takedown lights remain off and ash only when
the Flash Takedown wire is activated, see “Setting
Conguration Options” on page 13.
Left Alley Green/Black Not available for Front or Rear CN SignalMaster.
Right Alley Orange/Red Not available for Front or Rear CN SignalMaster.
Takedown White/Black Provides white light to the front. Overrides Flash
Takedown lights and Front Cutoff.
Low Power White/Black/Red Dims the lights approximately 50 percent to prevent
blinding approaching drivers. Low Power is only
available in Modes 1 and 2 and is disabled when
switched to another ash pattern, including Mode 3
and Intersection.
Intersection (SW-2
Switch 3 in the up
position)
Scene Light, Left
(SW-2 Switch 3 in
the down position)
Blue/Black Typically a high activity pattern. Overrides all three
priority modes. Scene Light, Left is unavailable.
Applying 12 Vdc to the Scene Light, Left wire turns
on the left half of the CN SignalMaster. Intersection
is unavailable.
Light bar Test Pattern
(SW-2 Switch 3 in
the up position)
Scene Light, Right
(SW-2 Switch 3 in
the down position)
Black/White/Red Flashes the LEDs sequentially and then ashes
the takedown and alley lights. Scene Light, Right is
unavailable.
Applying 12 Vdc to the Scene Light, Right wire
turns on right half of the light bar. Light bar Test
Pattern is unavailable.
*See document P/N 2562248 for instructions on setting these options in the Serial
Interface Module
NOTE: If you are installing a Front and Rear CN SignalMaster on the same vehicle, you
can use one interface box with a CAT5 splitter (P/N 1751531A).

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Installation, Operation, and Service Manual
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Installing the CN SignalMaster
Setting Conguration Options
The CN SignalMaster has three configuration options that are selectable with DIP
switches on the light bar’s control board. Table 3 describes the options. See “Figure 2
DIP switches on the CN SignalMaster controller PCBA” on page 14 for the locations
of DIP switches on the controller PCBA in the CN SignalMaster.
Table 3 CN SignalMaster DIP switch settings
DIP Switch
Position
Description of Option
SW1 Sets an eight-head (OFF) or six-head (ON) CN SignalMaster with DIP Switch 3 OFF (REAR).
With Switch 3 ON (Front), Switch 1 sets the lightheads that turn on when a Steady Burn input
is applied. The default position for Switch 1 is OFF for driver side/passenger side Steady Burn
(Positions 2, 6) of the Front CN SignalMaster. Turn Switch 1 to ON for driver-side only Steady
Burn (Position 2).
SW2 DIP Switch 2 switches between light head colors. To get amber SignalMaster patterns in LED
light head assemblies, including White/Amber, Blue/White/Amber, or Red/White/Amber, DIP
Switch 2 must be ON. Otherwise, the light bar will ash color combinations that do not include
amber.
SW3 Switch 3 has three functions:
• Activating a front-mounted or rear-mounted CN SignalMaster
• Performing an LED scan to ensure that an LED board ashes the correct colors after it is
installed
• Changing the Device ID to enable the CN SignalMaster to operate independently of the
light bar (available with the SmartSiren Platinum Conguration Software)
Choosing to Activate a Front- or Rear-Mounted CN SignalMaster
To activate a front-mounted CN SignalMaster, set Switch 3 ON.
To activate a rear-mounted CN SignalMaster, set Switch 3 OFF.
Performing an LED Scan
When an LED board is changed, an LED scan must be done to enable the LED board to ash the
correct colors.
To perform the scan:
1. Disconnect the red power (BAT+) wire to the CN SignalMaster and maintain power to the
control head.
2. Change the position of DIP Switch 3 and turn power ON to the CN SignalMaster. The CN
SignalMaster emits a short ash to indicate the LED scan is done.
3. To return DIP Switch 3 to its original function, repeat the scan.
Changing the Device ID
The default setting for the CN SignalMaster is to respond to light bar commands. For example, if
the system includes a light bar and a CN SignalMaster, both devices perform the same functions.
The SmartSiren programming software enables you to program the control head to send a set of
commands dedicated only to the CN SignalMaster, making its operation independent of the light
bar.
To reset the control head to the default setting, perform an LED scan as described above.
SW4 Sets the ability to power the network cable for other devices. The default is OFF. DIP Switch 4
should be set only if the main power cables are turned on through an ignition-activated relay. If
powering other devices, such as the Six-Button Serial Controller, set DIP Switch 4 to
ON. For more information, see the instructions included with the network-powered device.

14 CN SignalMaster™
Federal Signal www.fedsig.com
Installing the CN SignalMaster
Figure 2 DIP switches on the CN SignalMaster controller PCBA
ON
14ON
14
SW4
SW3
SW2
SW1
290A6977
For the location of the controller PCB,
see Figure 4 on page 16 and Figure 5 on page 17.
Testing the Light Bar
LIGHT HAZARD: To be an effective warning device, an emergency warning
system produces bright light that can be hazardous to your eyesight when
viewed at a close range. Do not stare directly into this lighting product at a
close range, or permanent damage to your eyesight may occur.
EXPLOSION HAZARD: To avoid a battery explosion, always disconnect the
negative battery cable rst and reconnect it last. Avoid causing a spark when
connecting near or to the battery. The gases produced by a battery can cause
a battery explosion that could result in vehicle damage and serious injury.
To check the light bar controls (see “Table 2 CN SignalMaster controls and wires from
the Serial Interface Module” on page 12):
1. Connect the 16 AWG black lead from the light bar to the vehicle battery’s ground
(–NEG) terminal and the 16 AWG red lead to the positive terminal.
2. Connect the black and black/white wires from the Serial Interface Module to the
vehicle battery’s ground (–NEG) terminal
3. Apply 12 Vdc to a control wire and to the ignition wire from the Serial Interface
Module.
4. After the installation, check the entire system to verify that the lights are flashing
properly and all light system functions are operating properly.

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Installation, Operation, and Service Manual
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Maintaining and Servicing the CN SignalMaster
Maintaining and Servicing the CN SignalMaster
This section has instructions for maintaining and servicing the CN SignalMaster,
including replacing the light bar PCBs and reflectors. For additional service and
support, call the Federal Signal Service Department at 800-433-9132, 7 am to 5 pm,
Monday through Friday (Central Time). For a list of common replacement parts, see
“Ordering Replacement Parts” on page 19.
Establishing a regular maintenance schedule for the CN SignalMaster extends its life
and ensures safety. Periodically ensure that the light bar operates properly and that
all mounting hardware is securely fastened to the vehicle. Inspect the reflectors for
cracks, crazing (hairline cracks), discoloration, and other defects.
Replacing a PCB
Depending on the installation, it may be necessary to remove the CN SignalMaster
from the vehicle
To remove the CN SignalMaster:
1. On the cable exit side, remove the two #10-32 6-lobe screws and the right-end
bracket. Holding both light assemblies (the Model CNSM4 has one light assembly),
slide them from the aluminum extrusion.
Figure 3 Exploded front view of Model CNSM8
290A6994
Aluminum Extrusion
#10-32 6-Lobe Screw (4)
Right End Bracket
To SML Connector on
Light Bar Controller
Light Assemblies (2)
2. Pull the cap(s), seal(s), and ROC board(s) from the lens.
3. Disconnect cables and remove the #6-32 Phillips screw to separate the PCBs.
4. Inspect the lip seal(s) to insure it is not torn, brittle, or damaged. Replace it
if necessary. For replacement parts, refer to Table 4 on page page 19.
Reassemble the light bar.

16 CN SignalMaster™
Federal Signal www.fedsig.com
Maintaining and Servicing the CN SignalMaster
Figure 4 Exploded rear view of Model CNSM8
Lens (2)
ROC PCB Assembly (2)
Location of Controller PCBA
CAT5
#6-32 Screw (2)
Cap (2)
Lip Seal (2)
Reflector (8)
290A6978
Power/Ground
Harness
Left Bracket
Right Bracket
#10-32 Six-Lobe Screw (4)
Aluminum Extrusion

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Installation, Operation, and Service Manual
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Maintaining and Servicing the CN SignalMaster
Figure 5 Exploded rear view of Model CNSM4
#6-32 Screw
Reflector
290A6995
Lens
ROC PCB
Assembly
Cap
Lip Seal
Location of
Controller PCBA
Power/Ground
Harness
CAT5
Right Bracket
Left Bracket
Aluminum Extrusion
#10-32 Six-Lobe Screw (4)
Figure 6 Exploded rear view of Model CNSM2X4R
Extrusion (2)
Bushing (3)
Foam Filler
ROC PCB Assembly
Smart Bracket PCB Assembly
6-32 Screw (2)
Dumb Backer PCB
Assembly
Lens (2)
Reflector (8)
Lip Seal (2)
Cap (2)
#10 Six-Lobe Screw (8)
Left End Cap (2)
Right End Cap
36-inch Board-to-Board Cable
144-inch Board-to-Board Cable
CAT5
Power/Ground
Harness
Right End Cap CNSM2X4R

18 CN SignalMaster™
Federal Signal www.fedsig.com
Maintaining and Servicing the CN SignalMaster
Replacing a Reector
CRAZING HAZARD: Crazed, cracked, or faded domes or reectors reduce the
light output and the effectiveness of the lighting system. Tops or reectors
showing this type of aging must be replaced. Failure to follow this warning
may result in bodily injury or death to you or others.
To replace a reflector:
1. To remove the PCB that holds the reflector, see “Replacing a PCB” on page 15.
2. Use a small Phillips screwdriver to press and release the two round tabs on the
reflector from beneath the PCB. Slide the reflector toward the rear of the PCB
(Figure 7).
3. Lift the rear of the reflector away from the PCB and remove it.
4. To install the new reflector, insert its front hooks into their slots on the PCB.
5. Bring the rear of the reflector down to insert its rear hooks through the PCB.
6. When the reflector rests on the PCB, make sure the rear hooks are fully inserted
and slide the reflector forward until its tabs snap into place.
Figure 7 Removing a reector
➀
➁
290A6978
➂
➃
Press the round tabs from
beneath the PCB and slide
the reflector back.
Lift the rear of the
Reflector to remove it.
➀
➁
Removal:
➄
Insert the front hooks in
the PCB.
Bring the rear of the reflector
down on the PCB and insert the
rear hooks into the PCB.
Slide the refector foward
until it snaps into place.
➂
➃
Installation:
➄
Rear Hooks

19
Installation, Operation, and Service Manual
Federal Signal www.fedsig.com
Getting Technical Support and Service
Getting Technical Support and Service
For technical support and service, please contact:
Service Department
Federal Signal Corporation
Phone: [phone]
Email: [email protected]
www.fedsig.com
Getting Repair Service
The Federal Signal factory provides technical assistance with any problems that
cannot be handled locally.
Any units returned to Federal Signal for service, inspection, or repair must be
accompanied by a Return Material Authorization (RMA). Obtain a RMA from a local
Distributor or Manufacturer’s Representative.
Provide a brief explanation of the service requested, or the nature of the malfunction.
Address all communications and shipments to the following:
Federal Signal Corporation
Service Department
2645 Federal Signal Drive
University Park, IL 60484-3167
Ordering Replacement Parts
This section contains a list of common and vehicle-specific replacement parts. To
order replacement parts, call Customer Support at 1-800-264-3578, 7 a.m. to 5 p.m.,
Monday through Friday (CT) or contact your nearest distributor or local dealer.
Table 4 Common replacement parts
Description Part Number
PCB Assembly Contact Federal Signal
Cable Assembly, Power, 15 ft 1461816
Cable, Network, 25 ft 1751357-02
Lens 8652133
Seal 865200996

2645 Federal Signal Drive
University Park, Illinois 60484-3167
www.fedsig.com
Customer Support
Police/Fire-EMS: 800-264-3578 • [phone]
Work Truck: 800-824-0254 • [phone]
Technical Support 800-433-9132 • [phone]