Ford Ranger Third Brake Light Not Working: Possible Reasons and Solutions

The third brake light on your Ford Ranger helps other drivers know when you’re braking, significantly when the side brake lights are obstructed. Therefore, learning the reasons this light stops working and providing a solution is ideal.

So, why is the Ford Ranger’s third brake light not working? Among the reasons the third light is not working on your Ranger include burned-out bulbs and corroded wiring. Also, the ground wire may be loose or its fuse blown. Diagnose further to determine the reason and provide a solution.

The third light is an important safety feature in your Ford Ranger, and the article aims to help you fix it. Read on to learn the reasons this light is not working and the solutions.

Ford Ranger Third Brake Light Not Working

The third brake light assembly has brake lights and two cargo lights on its sides. The third brake light comes on with the other two side brake lights, while the cargo lights come on when needed. However, in some models, these lights illuminate when reversing the truck.

Like most vehicle parts, this light develops problems and fails to work. 

• Some owners of the third-generation model reported water getting into the truck’s headliner through the seal in the third brake light housing.
• However, the most impactful problem is the third brake light not working when braking, along with the other two.  

Reasons Ford Ranger’s Third Brake Light Is Not Working

The reasons the third brake light is failing on your Ford Ranger include;

1. Burned Bulbs

Burned bulbs are one of the reasons the third brake light doesn’t work on your Ford Ranger. The bulbs usually burn due to an electrical short circuit, either on damaged wiring or due to moisture exposure in the housing.

Diagnosis

To confirm whether you have a burned-out bulb, perform further diagnosis. Follow the steps below;

• Step 1. Access the bulb
• Step 2. Remove the bulb from the holder
• Step 3. Check for burnt filaments
• Step 4. Check for corroded holders

Solutions

Replace the burned-out bulbs if the diagnosis shows that it’s the reason the third brake light is not working. Follow the steps below;

• Step 1. Access the third brake light by removing the top cover using a flat tool. Some earlier models didn’t have this cover, especially the first three generations.
• Step 2. Open the two Phillips head screws using a screwdriver.
• Step 3. Pull out the assembly.
• Step 4. Twist a quarter turn left to open the bulb holder to remove the bulb.
• Step 5. Install a new bulb and turn it clockwise on the holder.
• Step 6. Test the new light.

Fixing the bulb is easy and will cost you below $10 if you do it. However, a mechanic will cost more than $50 to diagnose and fix.

2. Corrosion

Another reason the third brake light is not working on your Ford Ranger is corrosion. Wires become corroded due to exposure to moisture. The seal on the first three Ford Ranger generations allows water into the assembly and the vehicle.

When moisture gets to the assembly, it can cause corrosion in the plug and the bulb holders, interfering with electric current flow.

Diagnosis

Usually, the cargo lights also don’t work when the plug has corrosion, so test them first. Access the assembly and unplug the plug to check for corrosion in the pins. Also, check inside the bulb holders to see whether they are affected by corrosion.

Solutions

If your diagnosis turns positive, showing the plugs and holders are corroded, follow the steps below to fix them.

• Step 1. Access the third brake light assembly
• Step 2. Unplug the plug connecting it to the vehicle
• Step 3. Dip the plugs into a cup with vinegar water for an hour
• Step 4. You can also use electric cleaners to clean the corroded plugs
• Step 5. Let them dry
• Step 6. Plug the light back on and test by pressing the brake pedal

Diagnosing and fixing corroded plugs for your third brake light and cargo lights should cost less than $30 for vinegar or an electric cleaner. However, a mechanic will cost more than $75.

3. Loose Ground

A loose ground wire is another possible reason the third brake light is not working on your Ford Ranger. The third brake light has its ground connection to the vehicle, and if it is loose, the circuit is incomplete, and the third brake light won’t work.

Diagnosis

Trace the ground wire from the third brake light to check whether there’s a loose connection or corrosion on it. Usually, the ground is connected to the vehicle’s body or frame.

On some models, the third brake light and cargo lamp lights use the same ground wire. Therefore, if the cargo lamp light also doesn’t work, it’s likely you have a bad ground wire.  

Solutions

Once you get the ground wire and it’s loose or corroded, fix it by following the steps below;

• Step 1. If the wire is screwed to the frame or body, unscrew it.
• Step 2. Remove rust from the connector and the location it rests on using sandpaper
• Step 3. Use a cleaner to help remove corrosion from the wire and body.
• Step 4. Put back the wire and screw it back on to ensure it fits.
• Step 5. Start the vehicle and test the third brake light.

Fixing loose ground wire can cost as low as $30 if you do it and more than $150 if you hire a mechanic to trace and fix it. If you have no idea how to go about it, hiring an expert will go a long way despite being a bit more expensive. 

4. Blown Fuse

In most Ford Ranger models, the third brake light has a fuse that protects it from short circuits and high currents. The light is not working because of a blown fuse if there were either of these events earlier.

Diagnosis

To confirm the fuse is blown, follow the steps below.

• Step 1. Locate the fuse box. In most Ford Rangers, it’s on the left side of the car under the hood. However, consult the user manual.
• Step 2. Locate the third brake light fuse, usually labeled CHMSL or CHMSL/Cargo.
• Step 3. Test the fuse with a test light by touching the holes with its probe.
• Step 4. The light on the tester should not light if the fuse is blown.
• Step 5. Take out the fuse and observe it if you don’t have a sensor. A dark metallic smear means the fuse is burned.

Solutions

If the diagnosis shows that the fuse is blown, follow the steps below to replace and fix it. While at it, remember to get a fuse of the same type and amperage as the current one to avoid unnecessary issues.

• Step 1. Turn off the vehicle
• Step 2. Locate the fuse box
• Step 3. Locate the third brake light fuse
• Step 4. Remove it using your fingers or fuse remover tool
• Step 5. Install the new fuse and ensure it is well-seated
• Step 6. Start the vehicle and test the third brake light

Diagnosing and fixing a blown fuse will cost you somewhere between $30 and $125, depending on whether you or the mechanic will do it. This allows you to choose whatever works best for you based on your budget and familiarity with the issue at hand. 

If you’re a Ford Ranger owner grappling with a non-functional third brake light, our article on 4Runner brake light not working concerns might offer insights that could be applicable to your situation. Additionally, if you’re dealing with a situation where your brake light stays on even when the car is off, our guide on brake light stays on when car is off issues is here to provide assistance. We understand the importance of maintaining proper vehicle lighting and addressing issues promptly, and our comprehensive resources are designed to help you navigate and resolve any challenges you may encounter.

FAQs

If you still haven’t figured out why the third brake light is not working on your Ford Ranger, follow the section below for further assistance.

Bottom Line

Some reasons Ford Ranger’s third light is not working include a blown fuse or burned-out bulbs. To be sure what is behind the problem, diagnose the vehicle further, following the steps in the article. Follow the appropriate solutions once you confirm what is causing the Ford Ranger third brake light not working. 

Most of the solutions are easy to do, and you can do it without the help of a professional. However, don’t hesitate to hire one if you’re not up for the task.