Before you begin. This procedure is general reference information, not professional advice. Equipment varies by manufacturer, model, and year. Always follow the documentation supplied with your equipment — where it differs from this page, follow the manufacturer. Verify that you have the tools, the working conditions, and the ability to do this task safely. If anything is unclear, if the equipment is damaged, or if the task exceeds your experience, stop and use a qualified professional. You are responsible for your own safety and for the outcome. This site accepts no liability for any loss, damage, or injury arising from the use of this information.
Specifications marked unverified could not be traced to a manufacturer source. Do not rely on them — obtain the value from your equipment documentation.
Summary
When one thing in a car stops working and everything else is fine — the cigarette lighter socket, the radio, one interior lamp — the cheapest explanation is a single blown fuse, and it is a part that costs less than a coffee. The job itself is genuinely easy: open the right fuse box, pull the right fuse with the little plastic puller the manufacturer already put in the car, look at the metal strip inside it, and push in a new one. What makes it go wrong is not the manual work. It is putting back the wrong fuse.
This page publishes the method and deliberately publishes no numbers. Every amperage rating, every fuse position and the location of the fuse panels themselves are specific to your vehicle, and they are printed on the fuse box lid and in your own owner's manual — so the page teaches you to read them there rather than guessing them here. The one rule that generalises is the one that matters: a replacement fuse must carry the same amperage rating as the fuse it replaces, because a bigger fuse does not fix anything, it just moves the weakest point from a part you can replace to the wires you cannot. The page also stops where the manufacturers stop. Bolted, main and high-current fuses are a dealer job, and a fuse that blows a second time is a fault, not a fuse.
Necessary equipment
| Item | Note |
|---|---|
| Owner documentation for your vehicle | The documentation gives the fuse map and the position of each fuse panel. |
| Fuse puller | Mazda and Kia put a fuse puller in the fuse block in the engine compartment. |
| Flashlight optional | The light at a fuse panel is often low. |
| Pen and paper optional | Record the fuse position and the ampere rating of the old fuse. |
| Replacement fuse material | The new fuse must have the same ampere rating and the same type as the old fuse. |
Prepare the vehicle
Estimated 2 min to 6 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
- Stop the vehicle on a level surface away from traffic.<1mReport a problem with step 1, Prepare the vehicle
- Set the parking brake.<1mReport a problem with step 2, Prepare the vehicle
- Stop the engine.<1mReport a problem with step 3, Prepare the vehicle
SET THE IGNITION TO OFF BEFORE YOU TOUCH A FUSE.
An electric arc can occur at a live fuse holder. An arc can burn you.
- Set the ignition to off.<1mReport a problem with step 4, Prepare the vehicle
- The switches for the lamps, the radio and the climate control must be off.
- Mazda and Kia tell owners to set the ignition to off before they touch a fuse.
- One Kia manual also tells owners to remove the negative terminal of the battery first.
- Get the documentation for your vehicle.1mReport a problem with step 5, Prepare the vehicle
- The documentation gives the position of each fuse panel.
- The documentation gives the ampere rating for each fuse position.
- Many vehicles have more than one fuse panel.
Find the fuse panel
Estimated 3 min to 6 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
- Find the fuse panel that your documentation gives for the dead circuit.2mReport a problem with step 1, Find the fuse panel
- The 2023 Mazda3 manual gives a fuse panel on the left side of the cabin.
- One Kia manual gives a fuse panel at the driver side and one in the motor compartment.
- Do not use the fuse panel of a different vehicle as a guide.
OPEN THE COVER OF THE FUSE PANEL CAREFULLY.
Too much force can break the tabs on the cover.
- Open the cover of the fuse panel.<1mReport a problem with step 2, Find the fuse panel
- Look at the fuse map on the cover.<1mReport a problem with step 3, Find the fuse panel
- The fuse map gives a name for each fuse position.
- The fuse map gives the ampere rating for each fuse position.
- Some vehicles print the fuse map in the documentation only.
Find the fuse for the dead circuit
Estimated 2 min to 5 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
- Find the name of the dead circuit on the fuse map.1mReport a problem with step 1, Find the fuse for the dead circuit
- If more than one item does not work, look for one fuse that they share.
- Find the position of that fuse in the fuse panel.<1mReport a problem with step 2, Find the fuse for the dead circuit
DO NOT REMOVE A FUSE THAT HAS A BOLT OR A NUT.
A fuse with a bolt is a high current fuse. Incorrect work on a high current fuse can cause an electric shock or a fire.
- If the fuse has a bolt or a nut, stop this procedure.<1mReport a problem with step 3, Find the fuse for the dead circuit
- Kia tells owners to speak to a dealer about a fuse with a bolt or a nut.
- Mazda tells owners to speak to a dealer about the main fuse.
Remove the fuse
Estimated 1 min to 3 min
- Find the fuse puller.1mReport a problem with step 1, Remove the fuse
- Mazda and Kia put a fuse puller in the fuse block in the engine compartment.
- If you cannot find the fuse puller, look in the documentation for your vehicle.
DO NOT USE A SCREWDRIVER OR ANOTHER METAL OBJECT TO REMOVE A FUSE.
A metal object can cause a short circuit. A short circuit can make sparks and heat. Sparks and heat can burn you.
- Pull the fuse straight from the fuse panel with the fuse puller.<1mReport a problem with step 2, Remove the fuse
- Hold the body of the fuse with the fuse puller.
Examine the fuse
Estimated 1 min
- Look at the metal strip in the fuse.<1mReport a problem with step 1, Examine the fuse
- The metal strip in a good fuse is continuous.
- The metal strip in a blown fuse has a break.
- Some blade fuses from Littelfuse have a clear housing. A clear housing shows the metal strip.
- If the metal strip has no break, install the same fuse again.<1mReport a problem with step 2, Examine the fuse
- A fuse with no break is not the cause of the dead circuit.
- Speak to a vehicle repair shop about the dead circuit.
Install a new fuse
Estimated 4 min to 32 min
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
USE A NEW FUSE WITH THE SAME AMPERE RATING AS THE OLD FUSE.
A fuse with a higher ampere rating does not protect the wires. The wires can become too hot and cause a vehicle fire.
DO NOT PUT A WIRE OR METAL FOIL IN A FUSE HOLDER.
A wire in a fuse holder gives no protection. The wires can burn and cause a vehicle fire.
- Read the ampere rating on the housing of the old fuse.<1mReport a problem with step 1, Install a new fuse
- Littelfuse stamps the ampere rating on the housing of the fuse.
- Littelfuse also gives a housing colour for each ampere rating.
- The stamped ampere rating is the value to use, not the colour.
- Compare the ampere rating on the fuse with the ampere rating on the fuse map.<1mReport a problem with step 2, Install a new fuse
- If the two values do not agree, speak to a vehicle repair shop.
- Get a new fuse with the same ampere rating and the same type.2mReport a problem with step 3, Install a new fuse
- Blade fuses have different physical sizes.
- A new fuse must fit the holder correctly.
- Mazda tells owners to use a genuine Mazda fuse or an equivalent fuse with the same ampere rating.
PUSH THE NEW FUSE FULLY INTO THE CLIPS.
A loose fuse can make heat at the contact. Kia tells owners that a loose fuse can cause a vehicle fire.
- Push the new fuse fully into the clips.<1mReport a problem with step 4, Install a new fuse
- Make sure that the new fuse is tight in the clips.<1mReport a problem with step 5, Install a new fuse
- If the new fuse is loose, speak to a dealer.
- Mazda tells owners that a loose fuse needs an expert.
- Close the cover of the fuse panel.<1mReport a problem with step 6, Install a new fuse
Do a test of the circuit
Estimated 2 min
- Set the ignition to on.<1mReport a problem with step 1, Do a test of the circuit
IF THE NEW FUSE ALSO BLOWS, DO NOT USE THAT CIRCUIT.
A second blown fuse is a sign of a fault in the circuit. The fault can cause a vehicle fire.
- Operate the circuit that did not work.<1mReport a problem with step 2, Do a test of the circuit
- If the new fuse also blows, stop this procedure.<1mReport a problem with step 3, Do a test of the circuit
- Kia tells owners to speak to a dealer immediately about a second blown fuse.
- Record the date, the fuse position and the ampere rating.1mReport a problem with step 4, Do a test of the circuit
- A record tells you if the same fuse fails a second time.
Terminology
This page uses one term for each item and holds it throughout, as ASD-STE100 requires. Equipment sellers and other guides use the names below for the same parts.
- fuse panel
- Also called: fuse box, fusebox, fuse block, fuse board, the box with all the fuses in it
- blade fuse
- Also called: car fuse, spade fuse, plug-in fuse, ATO fuse, mini fuse, the little plastic fuse
- ampere rating
- Also called: amp rating, amperage, amps, fuse size, the number on the fuse
- fuse map
- Also called: fuse diagram, fuse box diagram, fuse chart, fuse layout, the sticker on the lid
- fuse puller
- Also called: fuse tool, fuse removal tool, fuse extractor, the little plastic tweezers
- blown fuse
- Also called: burnt fuse, burned out fuse, popped fuse, broken fuse, the fuse went
- high current fuse
- Also called: main fuse, multi fuse, cartridge fuse, bolt-down fuse, the big fuse
When to use a professional
Do not remove a fuse that has a bolt or a nut. Do not replace the main fuse. Mazda tells owners that the main fuse is a high current fuse. Incorrect work on a high current fuse can cause an electric shock or a fire. Speak to a dealer about a high current fuse.
If a new fuse also blows, stop this procedure. A second blown fuse is a sign of a fault in the circuit. Do not use that circuit. Speak to a vehicle repair shop about the fault. Kia tells owners to speak to a dealer immediately about a second blown fuse.
If a new fuse is loose in the clips, stop this procedure. Mazda tells owners that a loose fuse needs an expert. Speak to a dealer about a loose fuse.
This procedure is for the low current fuses of a vehicle only. Do not use this procedure on the electrical installation of a building. Speak to a qualified electrician about the electrical installation of a building.
Common questions
Can I put a higher amp fuse in?
No, and this is the single reason the page exists. Kia's owner's manual puts it in a warning: never replace a fuse with anything but another fuse of the same rating, because a higher capacity fuse could cause damage and possibly a fire. A fuse is deliberately the weakest part of the circuit — it is designed to fail first so the wiring behind it does not. Fit a bigger one and the wiring becomes the weakest part instead, and wiring is buried in the car rather than sitting in a clip you can reach. If a fuse of the correct rating will not stay intact, the answer is a repair, not a bigger fuse.
Where is the fuse box in my car?
There is more than one, and where they are is model-specific. Mazda's 2023 Mazda3 manual describes fuses on the vehicle's left side inside the cabin plus a fuse block under the hood. A Kia owner's manual describes two or three panels: one in the driver's side panel bolster and one in the motor compartment near the battery. Some vehicles put a panel behind a kick panel, in the glovebox, or in the trunk. Your own owner's manual names the ones your car has, and the fuse map on each lid tells you what is inside it.
My cigarette lighter socket stopped working. Is it the fuse?
It is the first thing worth ruling out, because a dead accessory socket with everything else working is exactly the pattern a single blown fuse produces. Both Mazda and Kia treat that circuit as a non-essential one in their manuals — each suggests borrowing a fuse of the same rating from it if you are stuck without a spare. Find the socket's fuse on the fuse map, pull it, and look at it. If the strip inside is intact, the fault is elsewhere and a repair shop is the next step.
How can I tell if a fuse is blown just by looking at it?
A blade fuse has a metal strip running between its two blades, and on a blown fuse that strip has an obvious break or a burnt gap in it. Littelfuse builds its ATOF blade fuses with see-through housings for exactly this reason — the company lists it as a feature, so you can see when the fuse has blown. Good light helps more than anything else. If you genuinely cannot tell, a continuity test with a multimeter settles it, and Littelfuse's blade fuses have checkpoints on top so the resistance can be measured without pulling the fuse at all.
What if I don't have a spare fuse?
Both manufacturers give the same stopgap, and both attach the same condition. Mazda's manual says that if you have no spare fuses you can borrow one of the same rating from a circuit not essential to vehicle operation, such as the audio or accessory socket circuit. Kia says the same thing and names the cigarette lighter fuse as an example. The rating still has to match — borrowing is about where the fuse comes from, not about relaxing the rule. Treat it as a way to get home and buy the right fuse afterwards.
Why does my fuse keep blowing?
Because the fuse is doing its job. A fuse that opens once may be bad luck; a replacement that opens too is telling you there is a fault drawing more current than the circuit was designed for — a chafed wire, a failed motor, a shorted accessory. Kia's manual is blunt about it: if the replacement fuse blows, this indicates an electrical problem, so avoid using the system involved and consult a dealer immediately. Do not keep feeding fuses into it, and do not fit a larger one to make it stop. This is the point where the page hands you to a repair shop.
Do the colours on car fuses mean anything?
Yes, but do not rely on colour alone. Littelfuse states plainly that colour coding indicates the amperage rating on its ATOF blade fuses, and the same convention is used across the industry. The same datasheet also lists high-contrast ampere stamps on the housings as a separate feature, and that stamped number is what you should actually read. Colours can be hard to judge in poor light, in a discoloured old fuse, or across different fuse series and sizes. Read the number, and cross-check it against the fuse map on the panel cover.
Do I need to disconnect the battery first?
The manufacturers do not agree, so this page will not pick one for you. Mazda's 2023 Mazda3 procedure asks only that the ignition is switched off and other switches are off, then goes straight to opening the fuse panel cover. The Kia manual registered here carries a note that goes further for the vehicle it covers: turn off the switches of all electrical devices and then remove the battery negative terminal. Those are genuinely different instructions for the same job, and averaging them would be inventing a third one. Follow your own vehicle's documentation, and ask a dealer if it does not say.
Related procedures
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- How do I test a fuse or check if a wire is broken with a multimeter
- What battery does my car take, and how do I read the group size and CCA rating before I buy a replacement
- How to test a car battery with a multimeter
- How to read the check engine light codes on your car with a cheap code reader
Sources
Every specification on this page is traced to one of these sources. Tier 1 is a manufacturer document, a published standard, or a government safety authority. See Standards for the full tiering rule.
- Tier 1Fuse Replacement — 2023 Mazda3 Owner's Manual, Owner Maintenance
- Tier 1Fuses — Kia Owner's Manual, Maintenance (US English, 2024, manual code CV1)
- Tier 1Inner panel fuse replacement — Kia Owner's Manual, Maintenance (US English, 2024, manual code KA4)
- Tier 1ATOF® Series Blade Fuses – Rated 32V, Fuse Datasheet
- Tier 1SAE J1284_197912 — Blade Type Electric Fuses (catalogue entry)
Revision history
Current version 1 · updated 2026-07-29 · next review due 2027-07-29
- v1 · 2026-07-29First draft. The sourcing band was tier1-per-unit and that is what the page publishes: the method, and no numbers. Every amperage rating, every fuse position and the location of each fuse panel are per-vehicle, so all five specifications publish as consult-the-documentation instructions with verified false and no digit in any value. The do-not-uprate rule, the no-wire-in-a-holder rule and the tight-fit rule come from Kia's owner's manual; the fuse-puller sequence, the same-rating replacement and the main-fuse boundary come from Mazda's 2023 Mazda3 owner's manual; the stamped ampere rating, the housing colour and the see-through housing come from the Littelfuse ATOF datasheet. Mazda and Kia disagree about the state of the vehicle before a fuse is removed — Kia's note adds removal of the battery negative terminal, Mazda's does not — and that disagreement publishes under rule 2 rather than being reconciled. Bolted, main and high-current fuses, and any fuse that blows a second time, are outside the boundary.
Corrections to this page are listed in the public corrections log. Reports that are credible and not yet verified are listed in the public errata register, and an open one renders above the step it concerns.
Comments and corrections
Found an error? A correction with a manufacturer source is applied and logged publicly. You can also write to corrections@fixchecklist.com.
Every step above carries its own report control, which tags the report with that step so a correction reaches the right place. For anything about the procedure as a whole — the order of the sections, a step that is missing, something that did not match your equipment — use this: report something about this whole procedure.