3
The main wire harness contains 8 wires which all have a specific purpose. Follow the wiring recommendations
enclosed for each wire. Wires not used should be released from the harness connector or taped off to prevent
accidental shorting.
HC4 10-Pin Main Harness
Light Brown
(-) Horn Output
Green
(-) Common Door Pin Input
Violet
(+) Common Door Pin Input
Blue
(-) Hood / Trunk / Auxiliary Trigger Input
Red/White (-) 300mA Programmable Channel 3 (Trunk) Output
White
(+/-) Parking Light Relay Output
Brown
(+) Siren Output
White/Fused
(+/-) Parking Light Relay Input
Open No Connection
Open Pr12VDC for Relay Connection
Light Brown Wire: (Pulsed Ground for Car Horn)
The light brown wire is a pulsed ground output designed to activate the vehicle’s existing car horn system in
place of or in addition to a siren sounding device. Connect the light brown wire to the negative trigger wire on
the vehicle’s horn relay.
WARNING! Maximum output of this wire is 300mA. Horn systems requiring positive voltage or more than
300mA to trigger the horn relay will require an additional relay to increase current capabilities.
White 10-Pin Connector
87
87a
86
85
30
Light Brown Wire
To +12V
To Horn
+12V or Ground Depending
on System Requirements
Fuse
Brown Wire: (Siren + Output)
Connect the brown wire to the positive wire from a siren. Ground the remaining wire from the siren for proper
operation.
Blue Wire: (Optional Grounding Sensor Input)
The blue wire is an instant grounding trigger input for optional hood/trunk grounded pin switches or any
electronic sensor.
Green Wire: (Grounded Door Pin Switch Input)
The green wire connects to the common wire of the vehicle that switches on the dome light. Normally this wire is
located at one of the door jamb switches. For some vehicles it may be necessary to connect the green wire directly
to the switched turn on wire at the dome light. The green wire connects to negative switched circuits only.
Wiring
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