TB0349A
Page 11 of 12
09/22/05
SERVICE
This unit is designed to provide years of reliable service under even the worst conditions. Many times there may
appear to be a problem with the unit when the true problem is in the speaker(s), controlled devices, or improper
installation. The following chart shows typical symptoms and possible causes.
A blown internal
siren
fuse doesn't necessarily mean that the unit is bad. If a speaker or speaker lead is shorted this
fuse will blow before the unit is damaged. Disconnect the SPKR leads and replace the fuse. If the unit itself emits a
low level sound when in the Yelp position it is OK. Check the speaker(s) or leads for possible shorting.
PROBLEMS
Symptom Possible
Cause
Check
No Power or siren output Power switch not turned on
Bad Speaker
Connector or connections loose
Internal siren fuse blown
Loose connection at power source
Does backlighting come on?
Do you hear a “pop” when turned on?
With siren on, yelp selected, listen for tone in amplifier.
Is an external fuse or circuit breaker used?
Are the power leads connected to a good buss?
No siren tone –
PA works
High Voltage Protection
Mic button stuck
Cutout activated
Cutout Polarity Option set wrong
The input voltage must be less than highest rating.
Does mic button release properly?
Does siren work when Cutout input is disconnected?
Is the CUT P option properly configured?
No PA
PA volume not set properly
Selector in Radio position
Try turning the PA volume control.
PA is not available in the Radio position.
Distorted siren sound
Speaker assembly loose
Intermittent Aux Input connection
Low vehicle voltage
Is the speaker bell or tip loose?
Is the Aux Input used and wired properly?
The input voltage must be greater than lowest rating.
Intermittent siren tone
High Voltage Protection
Connector or connections loose
Loose connection at power source
Mic button activation
Circuit breaker in supply
connection
Is the vehicle voltage regulator working properly?
Is the connector tight on the back of the unit?
Check for loose leads back to power source.
Is something lying on the microphone?
Is a circuit breaker used with at least 50A rating?
Horn or Manual or
Phaser stuck on
Horn switch stuck
Man/Phsr switch stuck
Aux Input improperly connected
Aux Input Polarity Option set
wrong
Does the Horn switch return fully when released?
Does the Man/Phsr switch return fully when released?
Is the Aux Input used and wired properly?
Is the AUX P option properly configured?
No Radio
Unit not connected to a radio
Radio volume too low
Is the radio connected properly to the unit?
Can you hear the radio in the vehicle?
Try turning the RAD volume control.
Wrong siren tone
Two-Tone option installed.
Aux Input set to wrong function
Is the T-T option jumper cut?
Is the AUX I option jumper configured properly?
Phaser not working
Phaser disabled
Is the PHSR option jumper cut?
Horn not working
Horn disabled
Is the trace cut that disables the Horn switch?
Automatic Siren not
working
Selector in Radio position
Automatic Siren disabled
Siren tone is not available in Radio position.
Is the internal red lead cut from lever switch board?
Automatic Siren in all
lever switch positions
No power to red lever switch lead
Do the lever switch relays turn on devices?
Check for power at red lever switch lead.
Lever switch not working
in all positions
No power to red lever switch lead
No ground at siren connector
Do the lever switch indicators light?
Check for power at red lever switch lead.
Lever switch not working
in some positions
Loose lever switch output
connection on lead
Does the lever switch indicator light?
Lever switch not working
in some positions
Loose lever switch output
connection on lead
Does the lever switch indicator light?
Lever switch output
stays on
Internal relay contacts fused from
overheating
Is the output current exceeding 20AMPS?
Rocker switch outputs
not working
No power to rocker switch
Loose rocker switch output
connection on lead
Is the corresponding fuse blown?
Does the rocker switch indicator light turn on?
