Car Security and Convenience / Basic Alarm Output Connections

The wires and connections listed below will not apply to all alarms. Some alarm installations will require the addition of diodes, relays, resistors, and/or other parts. Always read your installation manual first.

Light Flash Outputs

Light Flash Light Flash (-) Output with out on board relay (diagram) Connect to one side of the coil of an SPTD relay with the other side connected to (+) 12V DC,  that when energized will turn the parking lamps on. Some vehicles will not require an additional relay, others will require more. Light Flash (+) Output with on board relay Connect one wire to the wire of the parking lamps that shows (+) 12 V DC when they are on. Connect the other wire to (+) 12V DC. Some vehicles may require one or more additional relays.

Illuminated Entry Outputs

Illuminated Entry Illuminated Entry (-) Output Negative Door Trigger (diagram) Connect to terminal #85 of an SPTD relay with the other side, terminal #86 connected to (+) 12V DC. Connect terminal #87 to ground and terminal #30 to the (-) door trigger. Illuminated Entry (-) Output Positive Door Trigger (diagram) Connect to terminal #85 of an SPTD relay, with terminals #86 and #87 connected to (+) 12V DC. Connect terminal #30 to the (+) door trigger. Illuminated Entry with on board relay Connect one wire to a vehicle door trigger and the other to ground for negative door triggers or to (+) 12V DC for positive door triggers.

Starter Interrupt Outputs

Starter Interrupts Starter Kill (-) Output (normally closed relay) (diagram) Connect to terminal #85 of an SPTD relay and the anode side of a diode if not using a pre wired socket that has one included. Connect the cathode side of the diode and terminal #86 to an ignition (+) source. Cut and connect the key side of the starter wire in the ignition harness to terminal #87a and the motor side of the starter wire to terminal #30. Starter Kill (-) Output (normally open relay) (diagram) Connect to terminal #85 of an SPTD relay and the anode side of a diode if not using a pre wired socket that has one included. Connect the cathode side of the diode and terminal #86 to an ignition (+) source. Cut and connect the key side of the starter wire in the ignition harness to terminal #87 and the motor side of the starter wire to terminal #30. Starter Kill with on board relay Cut and connect the key side of the starter wire in the ignition harness to one wire (usually specified) and the motor side of the starter wire to the other wire.

Door Lock Outputs

Door Locks Door Lock Outputs (diagrams) First determine the switch type then wire accordingly. Most of today's alarms have at least a pair of negative outputs that will provide enough current to energize the coil of one relay each. Some will provide both positive and negative outputs (may require adding diodes), or a dip switch to select polarity. Others may have two on board relays with wires for the normally closed, normally open, and common terminals of each relay. These are the most common types of door lock outputs, but I could go on. If you are uncertain of which type of outputs your alarm has, if any, after reading your owner's manual, use your meter. Check for positive DC voltage first.

Horn Output

Horn Horn Blow (-) Output Connect to the wire from the horn switch that shows ground when the switch is pressed. Some vehicles will require the use of a relay to supply (+) 12V DC to the horn it self. If the horn does not sound when the key is in the off position, you will need to add at least one relay.

Alarm Auxiliary Outputs

2nd Channel / Auxiliary 2nd Channel / Auxiliary (-) Output(s) These negative outputs will be connected to the coil of a relay or another module to control any number of functions of the vehicle or other components; trunk release, garage door opener, remote start, windows up and/or down, etc. These outputs may also be a pulsed or latched type. Some alarm and keyless entry systems may have one or the other or both. Check your installation manual first.

Siren Outputs

Siren Siren (-) Output If the alarm you are installing has this output connect it to the negative wire of the siren. Connect the positive wire of the siren to (+) 12V DC. See your installation manual for more info. Siren (+) Output If the alarm you are installing has this output connect it to the positive wire of the siren. Connect the negative wire of the siren to ground. See your installation manual for more info.

LED Outputs

LEDs Light Emitting Diodes Many of today's alarms have a port to plug the LED directly into them. If yours does not, there will be a dedicated wire that has a positive or negative output. If the output is positive, connect it to the positive wire of the LED and connect the negative wire of the LED to ground. If the output is negative, connect it to the negative wire of the LED and connect the positive wire of the LED to (+) 12V DC. Do not connect the wires of an LED to both (+) 12V DC and ground without a resistor.

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