Installing fog lights in your vehicle can greatly improve visibility during foggy weather conditions. However, to ensure their proper functioning, it is essential to have a reliable wiring system. In this article, we will discuss the 5 pin relay wiring diagram for fog lights, along with its installation process and frequently asked questions.
What is a relay?
A relay is an electronic switch that allows a low-power signal to control a high-power device. In automotive applications, relays are commonly used to switch on/off high-power devices, such as fog lights, headlights, and horns. They also protect the low-power control devices from high current damage.
How does a relay work?
A relay consists of an electromagnet, a set of contacts, and a spring-loaded armature. When current flows through the coil, it generates a magnetic field that attracts the armature towards it, closing the contacts. When the current is stopped, the spring pushes the armature back, opening the contacts. This mechanism allows a small current to control a large current, without the need for a direct electrical connection.
What are the types of relays?
There are several types of relays available in the market, based on their application and construction. The most common types of relays used in automotive applications are:
| Type | Description |
|---|---|
| SPST | Single Pole Single Throw relay has one normally open contact that closes when the coil is energized. |
| SPDT | Single Pole Double Throw relay has one normally open contact and one normally closed contact that change position when the coil is energized. |
| DPST | Double Pole Single Throw relay has two normally open contacts that close when the coil is energized. |
| DPDT | Double Pole Double Throw relay has two normally open contacts and two normally closed contacts that change position when the coil is energized. |
What is a 5 pin relay?
A 5 pin relay is a DPDT (Double Pole Double Throw) relay, which has two normally open contacts and two normally closed contacts that change position when the coil is energized. It also has one additional pin, which is the control pin, used to switch the relay on and off.
How to wire a 5 pin relay for fog lights?
Wiring a 5 pin relay for fog lights involves connecting the control pin to a switch, the battery ground to the relay, the battery positive to the relay, the fog light positive to the relay, and the fog light ground to the vehicle’s body. Follow the steps below to wire a 5 pin relay for fog lights:
Step 1: Disconnect the negative battery terminal
Before starting any electrical work, it is essential to disconnect the negative battery terminal to prevent any accidental short circuits.
Step 2: Mount the relay
Select a suitable location to mount the relay, preferably near the battery or the fog lights. Use screws or zip ties to secure the relay in place.
Step 3: Wire the control pin
Connect one end of a wire to the control pin of the relay and the other end to a switch. The switch can be a toggle switch, a push-button switch, or any other suitable switch that can handle the required current and voltage.
Step 4: Wire the battery ground
Connect one end of a wire to the ground pin of the relay and the other end to the negative battery terminal.
Step 5: Wire the battery positive
Connect one end of a wire to the positive pin of the relay and the other end to the battery positive terminal.
Step 6: Wire the fog light positive
Connect one end of a wire to the normally open contact of one of the poles and the other end to the positive terminal of the fog light.
Step 7: Wire the fog light ground
Connect one end of a wire to the vehicle’s body and the other end to the negative terminal of the fog light. Alternatively, connect the fog light negative directly to the battery negative terminal.
Step 8: Test the wiring
Reconnect the negative battery terminal and test the wiring by switching on the control switch. The fog light should turn on and off with the switch.
FAQ
Do I need a relay for fog lights?
Yes, it is recommended to use a relay for fog lights as it protects the low-power control devices, such as switches and sensors, from high current damage. It also provides a more reliable and efficient wiring system for the fog lights.
What gauge wire should I use for fog lights?
The wire gauge depends on the current rating of the fog lights and the length of the wiring. Generally, for a current rating of 5-10A and a length of up to 10ft, 16-18 gauge wire is suitable. For longer lengths or higher current ratings, a larger gauge wire should be used.
How do I aim my fog lights?
To aim your fog lights correctly, park your vehicle on a level surface, 25 feet away from a wall, and turn on the fog lights. Adjust the lights so that the top of the beam is 4 inches below the center of the fog light lens and the center of the beam is aimed straight ahead.
Can I wire multiple fog lights to one relay?
Yes, multiple fog lights can be wired to one relay, provided that the combined current rating of the fog lights does not exceed the current rating of the relay. The wiring diagram will also differ based on the number and type of fog lights used.
Can I use a 4 pin relay for fog lights?
Yes, a 4 pin relay can be used for fog lights, provided that it is a DPDT (Double Pole Double Throw) relay, similar to a 5 pin relay. The wiring diagram will also differ based on the type of relay used.
Conclusion
Wiring fog lights with a 5 pin relay is an effective way to ensure their proper functioning and protection. By following the above steps and guidelines, you can easily wire your fog lights with a 5 pin relay and enjoy enhanced visibility during foggy weather conditions. Remember to always disconnect the battery terminal before starting any electrical work and to use the recommended wire gauge for your fog lights.
