How to Choose Quality Fuses

Reviewed by

Richard McCuistian, ASE Certified Master Automobile Technician

Technical Reviewer at CarParts.com

Written by CarParts.com Research Team - Updated on March 4th, 2024

Reading Time: 6 minutes
Summary
  • Not all fuses are built equal. They come in different types, sizes, and colors. The capabilities of a fuse will vary according to these factors.
  • A fuse has a fusible link, a strip of metal that can conduct electricity. When an electric current passes through the link, the metal heats up. An electric current that exceeds the fusible link’s maximum load rating will cause the fuse to blow, stopping the current flow.
  • You can tell that a fuse is blown by looking inside the part and observing the fusible link. If the link shows visible signs of damage or melting, it’s probably blown.

Fuses are some of the simplest and most disposable automotive parts. Yet they are also a critical part of your car’s electrical system. They protect more complex electrical parts and electronics from dangerous surges of excess power or from electrical shorts. Of course, when a fuse blows, it needs to be replaced.

It’s crucial to get a fuse that you can depend on to keep your car’s electronics and electrical parts safe. Picking the wrong replacement part can lead to major problems. So how can you tell quality fuses from the rest? Find out what you need to think about when selecting a new fuse.

The fuse in this photo was photographed just as it opened the circuit due to a current surge caused by a short circuit within the throttle control module on a 2003 Chevrolet Silverado. This is what fuses are for. | Image Source: Richard McCuistian

What To Look For in Quality Fuses

Not all fuses are built equal. They come in different types, sizes, and colors. The capabilities of a fuse will vary according to these factors.

The clearest way to make sure you’re getting good fuses is to buy a known good brand. This is not to say none of the other fuse manufacturers make good fuses, but there are so many brands out there that you can’t assume they’ll protect some of the more sensitive circuits.

The clearest way to make sure you’re getting good fuses is to buy a known good brand.

Richard McCuistian, ASE Certified Master Automobile Technician

Here are a few factors you should take into consideration when choosing quality fuses:

Type

The majority of modern vehicles built after 1980 use blade fuses.  The blade fuse gets its name from the pair of flat, blade-like prongs or terminals that plug into the fuse box’s sockets. It also has a colored plastic body.

Blade fuses come in half a dozen different types. Here is a list of them:

  • Micro2 fuses are the smallest blade fuses. They are long and slender.
  • Micro3 fuses stand out as the type with three prongs.
  • Although not as small as micro2 fuses, low-profile mini fuses are compact, with short prongs.
  • Mini fuses look similar to low-profile mini fuses save for their prongs, which are longer.
  • Regular fuses set the benchmark for automotive blade fuses. Only maxi fuses are bigger than these standard-issue parts.
  • Maxi fuses are the largest type. Designed to handle high currents, they are heavy-duty parts.

When replacing a blown fuse, pick a product of the same type. You can usually find the details on the cover of the fuse box. If you can’t find the information on the lid, refer to your owner’s manual. You can also ask the manufacturer about your car and what type of fuse it uses.

Current Rating

Current rating refers to the maximum continuous current that can pass through the fuse without blowing the part. Also called fuse rating, it uses amps (A) as its unit of measurement.

Depending on the type of fuse, the current rating can start as low as 0.5A. The fuse rating initially increases by 1A for the first five, 2.5A for the next two, 5A for the following 3, and 10A for the rest.

Most blade fuses come in the following ratings:

  • 1A
  • 2A
  • 3A
  • 4A
  • 5A
  • 7.5A
  • 10A
  • 15A
  • 20A
  • 25A
  • 30A
  • 40A
  • 50A
  • 60A
  • 70A
  • 80A

Some fuse types start at a different current rating than the others. One notable example is the maxi fuse, the largest type designed for heavy duty performance. The lowest current rating for maxi fuses is 20A. They can handle loads as high as 120A.

All-glass (AGC) fuses have a maximum current rating of 50A, much lower than the maxi fuse’s load.

Need to determine the current rating of a fuse? Check its body. The fuse rating is on the plastic part. Otherwise, you should consult your owner’s manual or ask an expert.

Coloration

Have you ever wondered about the color of a fuse’s body? The color indicates the fuse’s current rating.

Here are the colors and associated current ratings for most blade fuses:

  • Dark Blue: 0.5A
  • Black: 1A
  • Grey: 2A
  • Violet: 3A
  • Pink: 4A
  • Tan: 5A
  • Brown: 7.5A
  • Red: 10A
  • Blue: 15A
  • Yellow: 20A
  • Clear: 25A
  • Green: 30A
  • Orange: 40A
  • Red: 50A
  • Blue: 60A
  • Tan: 70A
  • Clear: 80A

Remember how some fuse types start and end at different current ratings? Some colors repeat, which can be confusing at times.

Consider the color yellow as an example. If a standard, mini, or maxi-fuse is yellow, it has a current rating of 20A. However, a yellow fuse link cartridge (a cylindrical fuse with either metal caps or blade contact points at both ends) has a rating of 60A.

In general, you should look for a replacement fuse that shares the color as your old one.

Size

The fuse’s size contributes to its current rating. Generally, the larger the device, the higher its fuse rating. Large fuses have thicker fusible links that can handle higher amps before they melt.

Notice that the fuse assortment on the left has various accepted industry seals while the assortment on the right has none of those symbols. With that in mind, the assortment with the industry endorsements is the clear choice. | Image Source: Richard McCuistian

What Are Car Fuses?

A fuse possesses a plastic body and two or three prongs/terminals. Held inside the body is a fusible link, a strip of metal that can conduct electricity. When an electric current passes through the link, the metal heats up. The higher the amps, the hotter the fusible link gets.

An electric current that exceeds the fusible link’s maximum load rating will melt the metal part. It causes the fuse to blow, cutting the circuit and stopping the current flow.

What Do Car Fuses Do?

Fuses protect electrical systems and electronics from damage caused by shorts and overloading. They also reduce the fire risk triggered by high-voltage currents overheating wiring and other parts.

How To Identify a Blown Fuse

A blown fuse will disrupt the performance of the parts that draw their power from the circuit. It’s usually a good idea to check the fuse box if one of your car’s electronic or electrically-powered parts acts up.

You can tell a blown fuse from an undamaged one. Take a look inside the part and observe the fusible link. If the link shows visible signs of damage or melting, it’s probably blown.

If you drive an older car that uses in-line fuses, look for a broken filament.

How To Replace a Blown Fuse

It’s easy to remove a blown fuse and install its replacement. Start by turning off the circuit to help prevent any accidents.

Next, find the fuse box. Its location can vary between vehicle models and model years. If you don’t know where it is, check your owner’s manual.

Once you find the fuse box, open its lid and look for the faulty fuse. Make sure it’s blown before removing it.

Plug the new fuse in the housing. Handle the part with care to avoid damaging it.

Close the fuse box. Then run your vehicle through tests to ensure that the new fuse is working properly. Adjust the fuse or get another one as needed.

Where to Get High-Quality Fuses for Your Vehicle

You know what to consider when shopping for a new fuse, but where’s the best place to buy one? If you’d rather avoid driving to local auto parts shops in search of the perfect replacement, why not shop online at CarParts.com?

With only a few clicks, you can find the right fuse replacement for your ride on our website. Use our vehicle selector to start shopping, and funnel the catalog results to match your preferences using the search filters.

Don’t worry about going over budget. All our fuses come with a low-price guarantee to help you get the best value for your money. They’re also on hand and ready to ship from a warehouse near you, so you can get your order in no time.

Check out our catalog and shop for new fuses today!

About The Authors
Reviewed By Richard McCuistian, ASE Certified Master Automobile Technician

Technical Reviewer at CarParts.com

Richard McCuistian has worked for nearly 50 years in the automotive field as a professional technician, an instructor, and a freelance automotive writer for Motor Age, ACtion magazine, Power Stroke Registry, and others. Richard is ASE certified for more than 30 years in 10 categories, including L1 Advanced Engine Performance and Light Vehicle Diesel.

Written By CarParts.com Research Team

Automotive and Tech Writers

The CarParts.com Research Team is composed of experienced automotive and tech writers working with (ASE)-certified automobile technicians and automotive journalists to bring up-to-date, helpful information to car owners in the US. Guided by CarParts.com's thorough editorial process, our team strives to produce guides and resources DIYers and casual car owners can trust.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.

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Published by
CarParts.com Research Team and Richard McCuistian, ASE Certified Master Automobile Technician
Tags: fuse