25
Installation, Maintenance, and Service Manual
Federal Signal
www.fedsig.com
Maintaining and Servicing the Allegiant
Troubleshooting the Light Bar
This section provides troubleshooting assistance for common problems. If you have
any questions left unanswered, call the Federal Signal Service Department at
1-800-433-9132, 7 a.m. to 5 p.m., Monday through Friday (CT).
Table 8 Troubleshooting tips
Problem
Corrective Action
The light bar
does not light
• Verify that the light bar’s Red and Yellow power lines (+BAT) and the
Black ground- power line (–GND) are properly connected to a good, fully
charged 12-volt battery. Check the 40 A fuse.
• Ensure that the ground connection from the light bar controller to the
aluminum extrusion is good.
• Check the fuses on the main bar controller.
• Reset the controller (page 23).
An LED
module does
not light
• Swap the LED board with good board to see if the board is bad.
• Check the connections of the cable that goes from the light bar controller
to the LED ROC board.
• Reset the controller (page 23).
Half of an LED
module does
not light
• Replace the ROC board that the LED is on.
• Reset the controller (page 23).
The light bar
turns off when
the Alley lights
turn on
• Ensure that the vehicle battery is fully charged.
• Verify that the light bar’s Red and Yellow power lines (+BAT) and Black
ground-power line (–GND) are properly connected to a good, fully
charged 12-volt battery.
• Check the Red and Yellow power lines (+BAT) and the Black ground-
power line
(–GND) connections in the light bar and vehicle.
• Reset the controller (page 23).
The light bar
has a delayed
response to
being shut off
• Reset the controller (page 23).
The Alley light
stays on with
ignition power
applied
• Ensure that there is no voltage on the corresponding control wire.
• To see if the ROC board is bad, swap it with a similar board.
• Swap the cables on the light bar controller outputs with a known good
output. If the problem moves to another halogen light, send the light bar
controller to Federal Signal for repair.
• Reset the controller (page 23).
