Help! Need Brake Light Switch Diagram

The brake light switch (also known as stop light switch) is a vital electrical part that informs drivers by turning the brake lights ON whenever hitting the brake. And, this switch can get bad and needs changing at any moment from when it starts to worn out.

Learning the spot with the wiring harness is something one can find through exploring the brake light switch diagram. Unfortunately, this topic is hardly explained in a simple manner and that’s the reason why most are still looking for it.

If that’s also you, then don’t get frustrated. Because we are here to help you out. In this guide, we’ll explain the brake light switch along with the part’s name. Plus, looking into a detailed guide might save hundreds of bucks. Let’s dive into the procedures.

It’s an integral part of your braking system and lets the driver behind you know that you’re slowing down. It also has a direct influence on your ABS, cruise control system, and more.

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Breaking Down the Brake Light Switch Diagram & Its Location

Most modern trucks including Ford, Chevrolet, and others usually have a brake light switch. And, it’s located right on top of the brake pedal (behind). Now, look at the given drawing of the location, and then we’ll get into the real talk.

The brake light switches have 2-pin, 4-pin, and 6-pin if looking closely that transfer the signals to function the red light on the back of the truck.

And, all of them look different which can be confusing if you aren’t aware of that. So, let’s go deep into each diagram of brake light switch. Ready?

2 Pin Brake Light Switch Diagram

By looking at the drawing, you can easily tell all the part names and their functions.

And also, the 2-pin brake light switch is commonly used on BMW, Mazda, and other truck models.

4 Pin Brake Light Switch Diagram

With the 4 pins in the brake light switch, the trucks show the beam as a warning on the backside.

In the given illustration, you will see the 4 pins (A, B, C & D) that refer to the ground, voltage, sensor, and brake light switch output, etc.

6 Pin Brake Light Switch Diagram

Circuit Figure	Wiring Harness Color
A	Light Green or Red
B	White or Dark Green
C	Pink or Light Green
D	Dark Green or White
E	Light Blue or Dark Green
F	Black or Dark Blue

As you can see in the diagram, the circuit of the brake light switch is referred to in alphabetical form. The (A) circuit is shown as the Brake Light Switch Sensor that signals the ABS module to know when you hit the brake.

Then, there’s the (B) circuit which is basically the Ground. Next to it, you’ll find the (C) figure that refers to the Speed Control Power Supply and its job is to divert the power of the motor when hitting the brake.

After that, the (D) figure is known as the Speed Control Brake Switch Output. On its right side, you will see the (E) circuit that refers to the Brake Light Switch Output. Lastly, figure (F) indicates the Fused B (+) circuit.

Frequently Asked Questions (FAQs)

How does a brake light switch work?

The brake light switch is a small electrical part that operates when you hit the brake. To explain in a simple way, most trucks have a spring in the brake pedal, and hitting this (spring-loaded brake pedal) using a foot causes the switch to turn off. And then, it causes the electrical circuit to shift the signal which turns on the brake lights.

What happens when the brake light switch fails?

If the brake light switch fails, it may show some weird problems. For example, the brake warning light doesn’t function rightly or the truck stays in ‘P’ (parking) mode.
And, it won’t end there as the truck can show the brake light turning on for a whole day even if you don’t hit the brake pedal.

How do you test a brake light switch?

To do that, just hold the sensor with the wire (one) while pressing the brake pedal and then test the other wire.
The test bulbs will lighten up to show the switch works fine. Conversely, if it doesn’t lighten up, then the switch needs replacement.

How much does it cost to replace the brake light switch?

It usually costs not more than $30 to $75 based on the quality and durability. However, if including the tax and other costs, the price might be higher.

Wrap Up

Still, not convinced with the information about the brake light switch diagram? Hope that’s not the case. It’s always better to know the parts rather than spending bucks on an auto shop just to find the brake light switch location and in some cases get stuck with having to repair things by them eventually. At least you’ll be able to give it a try at fixing yourself.

All the drawings given above will give a deeper insight so that you can easily locate the brake light switch. Hopefully, this guide didn’t disappoint you to deliver an explanation of the things you were looking for. Keep up the good work and take care!

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Help! Need Brake Light Switch Diagram