Go-Parts
Cart 0
Your cart is empty
Add an item to see it appear here.
Wrenchy
Go-Parts Garage
Expert guides for diagnosing, troubleshooting, and replacing auto parts Expert guides for diagnosing and replacing auto parts
Browse All Articles →
🎬 Helpful Videos 🛍️ Shop This Part

1987 GMC V2500 Brake Light Switch: A Complete Replacement Guide

Don't get left in the dark; learn the signs of a failing brake light switch and how to choose the right replacement for your truck.

3 minutes to read 1987-1987 GMC V2500
Difficulty
2/5
Est. Time
0.5 hrs
DIY Doable?
✅ Yes
Shop Labor
$50-$100
Used OEM Price
$10-$25
🚫 Do not drive — Driving without functional brake lights is extremely dangerous and illegal.
Key Takeaways
  • A failing brake light switch is a critical safety issue; replace it immediately if your brake lights don't work.
  • Symptoms include brake lights not working, staying on and draining the battery, or cruise control issues.
  • Replacement is simple and DIY-friendly, with the main difficulty being access under the dashboard.
  • If a new switch doesn't fix the problem, the turn signal switch in the steering column is the next most likely cause.
The brake light switch on your 1987 GMC V2500 is a small but vital electrical switch. It is mounted on the brake pedal assembly under the dashboard. When you press the brake pedal, the switch closes a circuit to send power to the brake lights, warning drivers behind you that you are slowing down. For trucks equipped with cruise control, this switch also sends a signal to deactivate the system as soon as you touch the brake pedal. The brake light circuit has constant power, so a faulty switch can cause issues even when the truck is off.

Is Your Brake Light Switch Failing?

A bad brake light switch on a Square Body truck like your V2500 usually fails in a couple of distinct ways. Because this part is critical for safety, recognizing the symptoms early is important.

🎬 Watch a breakdown of common symptoms and replacement costs.
  • Brake Lights Don't Work: The most dangerous symptom is when the switch fails to send power, and your brake lights don't turn on at all. This makes you invisible to other drivers when you're stopping or slowing down.
  • Brake Lights Stay On: The switch can also fail in the 'on' position, leaving the brake lights illuminated even when your foot is off the pedal. This can confuse other drivers and will drain your battery, as the circuit is always live.
  • Cruise Control Malfunctions: If you have cruise control, a bad switch can prevent it from engaging or, more dangerously, prevent it from turning off when you hit the brakes.

Pro Tip: Check the Turn Signal Switch

On these 1980s GM trucks, the power for the brake lights is routed through the multi-function turn signal switch in the steering column. If you replace the brake light switch but still have no brake lights, the problem may be the turn signal switch itself. This is a common point of failure on older vehicles.

Choosing the Right Aftermarket Brake Light Switch

For a straightforward part like a brake light switch on a 1987 V2500, there is little practical difference between an OEM part and a quality aftermarket replacement. The key is choosing a reputable brand to avoid premature failure. Given the low cost of the part, it's worth spending a few extra dollars for a trusted name.

Available Brands:

  • Standard Ignition (SMP): A well-known and trusted brand in the aftermarket, Standard often produces parts that meet or exceed original specifications. They emphasize quality control and use durable materials like copper alloy conductors and high-impact housings to ensure longevity. This is generally considered a reliable, top-tier choice.
  • Rostra Powertrain: Rostra is a known manufacturer, particularly for electronic components. While less information is available specifically for their brake light switches, they are an established company in the automotive aftermarket.
  • Skyward: Skyward positions itself as a supplier of quality-certified (ISO 9001) parts, cooperating with over 100 OEM factories. They perform quality checks before shipment, aiming to be a reliable value-oriented option. This brand likely falls into the economy or standard-tier category.
Brake Light Switch Cost (1987 GMC V2500)
Part Type Estimated Price Range
New Aftermarket $5.40 - $29.97
Shop Labor $50 - $100

Frequently Asked Questions (FAQ)

Is it hard to replace the brake light switch myself?

No, this is a DIY-friendly job that requires basic hand tools. The biggest challenge is the awkward position you have to be in, working under the dash above the brake pedal. You will likely need to remove a lower dash panel for access.

Where is the brake light switch located?

The switch is mounted to the brake pedal support bracket, located up under the dashboard. You will see it attached to the pedal arm, where it is activated as the pedal is pressed.

🎬 Learn how to access and maintain your Square Body brake pedal.
Why did my battery die overnight?

If the brake light switch gets stuck in the 'on' position, it will keep the brake lights lit continuously. Since the brake light circuit has constant power directly from the battery, it will drain the battery even with the truck turned off.

🎬 See how to fix brake lights that stay on.
Do I need to adjust the new switch?

Many modern replacement switches are self-adjusting. The installation instructions will specify the procedure, but it often involves installing the switch, pressing the brake pedal, and then pulling a tab or lever on the switch to set its position correctly. Always follow the instructions included with your specific part.

SYMPTOMS OF A BAD BRAKE LIGHT SWITCH
SYMPTOMS OF A BAD BRAKE LIGHT SWITCH
4 Symptoms of a Bad Brake Light Switch (and Replacement Cost)
4 Symptoms of a Bad Brake Light Switch (and Replacement Cost)
Symptoms of a Bad Brake Light Switch You Shouldn’t Ignore
Symptoms of a Bad Brake Light Switch You Shouldn’t Ignore
(Fix) How to replace Brake light Switch . Brake lights stay on
(Fix) How to replace Brake light Switch . Brake lights stay on
1973-87 Squarebody Chevy & GMC - Squeaky Brake Pedal Repair, Removal, Maintenance & Installation
1973-87 Squarebody Chevy & GMC - Squeaky Brake Pedal Repair, Removal, Maintenance & Installation

Technical Specifications

OEM Part Numbers: J201466

Typically a 2-terminal switch activated by the brake pedal arm. Note whether your vehicle has cruise control when ordering, as some switches are specific.

Wrenchy
Article researched & written by
Go-Parts' AI research assistant. Every article is backed by live web research, verified OEM data, and real technician knowledge — so you get accurate, up-to-date information you can trust.
Meet Wrenchy → Updated Apr 19, 2026

The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.

Year Coverage
This article covers the Brake Light Switch for:
  • GMC V2500: 1987
In this article
🎬 Helpful Videos
Jump to ▴

Email This Guide

We'll send you a link to this article so you can read it later or share it.

Added to cart · Part