It would be 3 wires coming out of the car driver s door locking systems there are a lock wire an unlock wire and a constant 12 volt positive wire.
Where to wire positive door lock trigger.
Positive trigger for doors ford vehicles that s it it even says this right in all their install manuals violet door trigger input.
Connect to the wire that only shows positive 12v dc when the brake pedal is being pushed.
Door locks actuators reverse polarity positive switch trigger type d relay wiring diagram.
How to wire your alarm to a car with negative door lock system.
This switch is usually located just above or behind the brake pedal onmost vehicles.
This wire will report zone 3.
To the coil of the respective relay.
How to wire your alarm to a car with negative door lock system.
Parking brake input.
Using a mechanical latching relay like the pcb latching relay pictured here you can use a single negative output to alternately lock and unlock the doors the mechanical latching relay only requires it s coil to be momentarily energized to change and maintain the opening or closing of it s contacts.
Both motor legs rest at ground at the relays.
To lock or unlock the vehicle polarity is changed on one motor leg via a positive pulse from a switch alarm keyless entry etc.
The following schematic diagram is common on many general motor s door locking system for cars it is a 3 wire positive trigger when you look at the door lock unlock switch in the driver s door.
This type of dome circuit is used in many ford products.