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How to Wire Door Lock Relays for Aftermarket Actuators

This article is a collaborative effort, crafted and edited by a team of dedicated professionals.

Contributors: Muhammad Baballe Ahmad, Mehmet Cavas, Sudhir Chitnis, and Zhen-ya Liu.

✓ Verified & Tested Information

This blog post will teach you how to wire door lock relays for aftermarket actuators. By following these simple steps, you can ensure that your door locks are properly wired and functioning.


Whether you are installing door locks on an older vehicle or a newer one, adding aftermarket actuators can be a difficult job. By following this guide, you can wire door lock relays for aftermarket actuators with ease. This guide covers the basics of relay wiring and will also explain why it is important to use relays whenever you are dealing with any type of electrical circuits.

Relays are a type of switch that uses an electromagnetically induced recoil in order to open or close its circuit. This recoil allows for remote operation, meaning that the relay’s contacts can be wired far away from where the user is controlling the relay, thus allowing for additional safety and security. In addition to allowing remote operation, relays also allow high currents of current to pass through its contacts without causing it to overheat and fail. This makes them ideal for connecting to something like an auto starter which draws large amounts of electricity when starting a car.

When setting up your door locks with aftermarket actuators, it’s important that you wire them up properly in order to ensure they work correctly and safely while also extending their lifespan. This guide will help walk you through all the necessary steps so that anyone can easily understand how to wire door lock relays for aftermarket actuators.

Tools Needed

For the installation of aftermarket door lock actuators, it’s important to use the proper tools. To begin, you will need a 12v power source, wire cutters and strippers, electrical tape and several feet of 16-gauge wire. The wire cutters should be used to separate the wiring harness into two sections: Black wires to ground and orange/blue wires for power. The power should not be taken from a battery source because it can cause automotive electrical system malfunctions.
If you are uncomfortable with the wiring process or lack experience in this area, we strongly recommend consulting a professional technician to complete the work in order to avoid damage or harm.
Once all of the necessary tools have been gathered, proceed with connecting one side of each relay terminal (85 & 86) to the black ground wire from your wiring harness; this connection will allow your car’s door locks to function correctly by using electricity to complete an electrical circuit when activated by 12 volts – generally supplied by a vehicle’s remote key fob or installed switch. The other side of each relay terminal (30 & 87A) should then be connected with 16-gauge wiring (with appropriate lengths for terminals 85 & 86). Using appropriate crimp connectors, secure one end of each newly installed 16-gauge wire at terminals 30 & 87A as well as terminals 87 & AUX/LOCK. After completing these connections, use electrical tape over all exposed connections in order to protect them from any possible short circuits or sparks due to exposed wiring and metal components.
Once all connections have been made and checked multiple times for accuracy – including double checking that both ends are securely soldered together – you are ready to start testing your system by simply supplying 12 volts through your remote key fob or installed switch in order for the power current (12v) activate all terminals in their respective positions allowing them accommodate your aftermarket actuators; once these settings are configured properly and all connections are verified twice over then everything is ready for install on either driver’s side/passenger’s side doors as desired!

Wiring the Relays

When wiring door lock relays for aftermarket actuators, it is important to understand how the relays should be wired. This is essential for ensuring proper operation and to prevent damage to the actuators. In this article, we will go over the different types of relays and how they should be wired in order to get the best possible results.

Connecting the wires

When wiring the door lock relays for aftermarket actuators, the connections must be made in a specific order for the system to function properly. To connect the wires, first gain access to the actuator assembly by removing the electronics enclosure and other obstructions that are covering it. Once this is done, identify each terminal on the rear of the relay and temporarily label them with their designated purpose (lock output, ground, etc.).

The wires from each door’s actuator should be connected to their respective terminals on one side of the relay; usually labeled with numbers such as 85 and 86. These should be connected in series where you will simply run a single wire from one terminal to another. Then use separate wires for each terminal (ground- 30; lock output – 87) or use a plug-in connector provided if it has been included in your kit. On some vehicles there may also be an additional pair of terminals labeled 87A and 87 which can also be used.

Now you will need to connect power (12V) and ground cables from your alarm system’s control unit or any other power source required by the relay configuration chosen, directly to its respective terminals (30 & 86). When all of these connections have been completed, you can reassemble all components before proceeding with programming or testing your relay system.

Connecting the power supply

Connecting the power supply to the relays is the first step when wiring door lock relays for aftermarket actuators. The power that is supplied will be used by the relays to control the actuator movement.

When connecting the power supply, you must take extra precautions as failure to properly connect it may cause damage to your equipment. Ensure that you follow these steps when setting up your power supply:
-Choose a DC source (battery, transformer or service panel), and mount it securely and away from flammable materials.
-Connect the positive (red) wire of the relay harness in parallel with the corresponding wire from your vehicle’s source harness; likewise, connect the negative (black) wire of the relay harness in parallel with its corresponding ground wire from your vehicle’s source harness.
-Secure these connections using electrical tape or crimp connectors, and make sure they are covered with a protective sleeve or heatshrink tubing so as to minimize contact with any physical objects in case you need to adjust or disconnect them later on.
-Carefully identify each connection inside a terminal block, then record each connection by labeling and documenting it accordingly if necessary.
-After all wiring has been done, use a multimeter to check for any unintended currents present in any of your wires; if nothing is detected move on to connecting other components such as switches and LEDs before testing your circuit’s functionality by powering it up slowly.

Testing the Relays

Before you can install the aftermarket door lock actuators, it is important to test the relays you are using. Testing the relays helps ensure that the actuators will function properly. This will help you avoid any problems down the road and help make your installation process easier. Let’s look at the steps for testing the relays for the aftermarket door lock actuators.

Testing for power

To test whether your door lock relays are working correctly and sending power to the actuators, you will need to check for a steady electrical current. To begin testing for power, you will first need to locate the wiring harness of your car’s relay. When you have located the wiring harness, you will need to disconnect the positive and negative terminals from their contacts as well as any load connectors that may be present. From here, you can use a multimeter to test the voltage in each of the individual terminals within the wiring harness.

Once you have connected a multimeter to two of these terminals, start testing for power by switching on each of your relays in turn. As long as each relay is functioning correctly and sending power through its circuit, then its respective terminal should have a steady current reading on your multimeter. However, if there is no reading or if it fails to maintain a steady current then this could indicate that either your relay is malfunctioning or that it has been incorrectly installed in relation to its respective actuator.

When testing for power within any type of circuit it’s important that extreme caution is taken as electricity can be dangerous when not handled properly – it is advised that when possible experienced professionals are consulted for assistance with electrical work such as this.

Testing for continuity

Testing for continuity is an important part of the process of wiring door lock relays when installing aftermarket actuators. The goal is to ensure that current is being sent to the correct contact pins on both sides of the relay, so that each actuator can be controlled by its own switch. To test for continuity, use a multimeter and set it to the lowest resistance setting. Then touch one probe to one contact pin on the relay and touch the other probe to each pin consecutively until you reach the last pin. The meter should indicate a low reading if there is continuity among all pins. Confirm that each wire is firmly attached to its respective pin as you move through this process, and make adjustments as needed in order to achieve accurate measurements.


In conclusion, the key to wiring your door lock relays for aftermarket actuators is to ensure that the wires are connected in the proper order. This can be done by referring to instruction manuals for your specific type of actuator and ensuring that you are using appropriately rated electric components. Additionally, it’s important to make sure that you have included all of the necessary safety features in your circuit. If you’re uncertain about any aspect of the wiring process, consult an experienced electrician or mechanic so that any mistakes can be avoided before they become costly repairs.

How to Wire Door Lock Relays for Aftermarket ActuatorsCheckout this video:

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