5 Common Symptoms To Detect A Bad Fusible Link [Explained]

The fusible link or the primary alternator fuse can turn bad or blow out because of excessive current flow caused by a short circuit or other internal malfunctioning issues. 

But do you know how to detect a blown or bad fusible link?

Detecting a bad fusible link can be confusing if you are not aware of the actual sign and symptoms of the bad fusible link. 

That’s why in today’s article, I will address the most obvious and common symptoms to detect whenever your vehicle’s fusible link has an issue.

What Sign You Should Look For To Detect A Bad Fusible Link?The most obvious sign that you might have a bad fusible link is when you face trouble using the automatic windows and central lock controlling option. 

You may also encounter issues with your vehicle’s wipers, radio, and music player control.

What Are The Other Symptoms To Detect A Bad Fusible Link?

Let’s learn about the other significant symptoms that help to identify when you have a bad or blown fusible link –   

1. Enable To Use The Automatic Option For Windows & Central Lock

When you notice that you are unable to use the automatic opening-closing windows. 

You also see that the automatic central locking option is not working. Instead of using the automatic option, you will have to lock and unlock the windows and central lock manually. 

2. Problem With Wipers

Another common symptom of a blown or bad fusible link is when you notice that your vehicle wipers fail to respond or work. 

Wipers supposed to keep your front view clear so that you can drive safely. 

But when your fusible link has an issue, the wipers will fail to work and keep your view clearer during rainy or snowfall days.

3. Radio & Music Failure

Most people tune on the radio for news updates or love listening to music while driving.

But when your fusible link turns bad, you will not be able to tune the radio or turn on the music player to enjoy your drive. 

Even if the radio or music player turns on, you might not be able to hear the sound clearly, or the music may constantly break in between.

4. Battery Failure

The fusible link is responsible to charge the vehicle’s internal battery, so when it turns faulty or bad, your vehicle battery will suffer from a lack of charge. 

It can be another very obvious symptom that you may need to replace the current fusible link.

A blown or faulty fusible link fails to charge the battery, and as a result, you may notice starting or operation issues on your vehicle due to battery failure.

5. Electrical & Lighting Issues:

Today’s modern and computer-controlled vehicles contain an array of electronics, which rely on charging system voltage. 

But a blown, broken, or damaged fusible link prevents the vehicle’s charging system from working properly and causes major electrical issues, especially on computer-controlled vehicles. 

As a result, the headlights, warning lights, check engine lights, or other lighting start to dim. 

If you notice any of the dashboard warning lights turn on or other vehicle lights turning dim, check your fusible link’s condition and replace, if needed.

These are the most common symptoms that will warn you whenever you have a failing fusible link.

What Should You Do After Detecting A Bad Fusible Link?

Whenever you encounter symptoms that indicate blown fusible link to cause the trouble, make sure to check and confirm the issue first. Then replace the fusible link. 

Replacing a blown or bad fusible link may sound like a very easy and straightforward task since all you need to do is cut off the damaged or broken link and install the new one.

However, if you are not well aware of the step-by-step procedures to do that, it can become really confusing and time-consuming.

Therefore, let’s learn the simple and easy steps to fix the fusible link problem-

Diagnosis & Confirm The Problem:

To diagnose, first, go under the hood to find the battery since the fusible link resides near the battery. Now, search for the smaller and more rubbery wire.

That is the fusible link you are looking for, in some wires, the tag name “fusible link” is printed on the wire.

So, you can confirm with the tag too. After confirming, inspect the wire for any possible damage.

Inspecting The Electrical Continuity:

You can also check the electrical connection with a voltmeter or multimeter‘s continuity setting. 

For this testing, clip a lead on the circuit’s one end and another lead to its opposite end. 

Now check whether there is any presence of continuity or not. 

If yes, the problem is not in the fusible link, and you need to check further for other possible reasons. 

But if not, then surely the fault is in the fusible link. 

While doing the electrical continuity test, remember to avoid using any 12-volt continuity test wand since not all circuits automatically contain 12 Voltages.

So, you should check and confirm before choosing the test wand.

Replacing The Fusible Link:

After proper diagnosis and inspection, if you are sure that all you need is to replace the fusible link, then follow the following process-

  • First, you need to find out the accurate fusible link that is compatible with your vehicle’s requirements and has more resistance than wiring as well. 
  • Next, you need to disconnect and remove the existing fusible link. 
  • After that, set the new fusible link in the old one’s place accurately and secure its connection.
  • Lastly, you need to weather-proof your connections. You can either by covering the joints with heat shrink tubing or use electrical tape to wrap the connections tightly.

Also, remember the fusible link length should be four times larger than the gauge wire size.

You can also use the new updated fusible links that feature pre-installed crimp connectors to simplify the installation process.

Is Replacing The Bad Fusible Link Typically Expensive?

No, fusible links that are currently available in the market are very affordable. Even one of the most popular and trusted brands, GM Motors offers their fusible link at $3.

Most people do the servicing and replacement of their fusible link during their annual vehicle maintenance, so there is nothing to worry about the extra cost. 

And if you can do the inspection testing and replacement task by yourself, you do not even need to think of the labor cost either.

How Often Should You Inspect Or Service A Bad Fusible Link?

Typically, you should inspect and replace the fusible link whenever you notice or encounter any earlier mentioned symptoms. 

However, according to the manufacturer and technical experts, all fusible links are advised to replace once a year. 

You need to inspect the fusible link for the possible presence of corrosion, soldered joint cracks, paint or chemical residue, and other foreign material. 

You can even replace it sooner if you want to. 

But generally, the best option is doing the inspection, testing, and replacement during the annual servicing of your vehicle.

Final Thoughts

Although a fusible link may look like a tiny piece of wire, it has a vital role in keeping your vehicle’s electrical components active and safe because fusible links are responsible for maintaining internal electric flow and preventing any damage due to current overflow. 

That is why you need to keep the fusible link updated, and these above-discussed symptoms will warn you whenever you need to check on your fusible link.

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