Find the fuse box and identify the blown fuse
Your car has at least one fuse box, usually under the dashboard on the driver's side or under the hood near the battery. Open the door or panel — most pull straight out or have a clip you release by hand. Inside you will see rows of small plastic fuses, each one protecting a different electrical circuit: headlights, wipers, power windows, cigarette lighter, and so on.
A blown fuse has a broken wire visible inside the plastic casing, or the wire looks blackened or melted. A good fuse has an intact wire running across the middle. If you cannot see the difference clearly, hold the fuse up to a light source. The fuse box lid usually has a diagram showing which fuse controls which system — find the one that matches the part of your car that stopped working, then look at that fuse.
Write down the amperage number printed on the fuse you are replacing. It will say 5A, 10A, 15A, 20A, or another number. You must replace it with a fuse of the exact same amperage. Using a higher amperage fuse can damage your car's wiring or start a fire. Using a lower amperage fuse will blow when ready.
Key Takeaways
- A blown fuse has a broken or blackened wire inside the plastic casing, while a good fuse has an intact wire running straight across.
- The fuse box is usually under the dashboard on the driver's side or under the hood, and the lid diagram tells you which fuse controls which system.
- You must replace a blown fuse with one of the exact same amperage — the number is printed on the fuse itself and on the diagram.
- Pull the fuse straight out with your fingers or a plastic fuse puller, then push the new fuse in until it clicks or sits flush with the box.
- If a fuse blows again within a few days, the electrical system has a deeper problem and needs professional diagnosis.
Remove the blown fuse with a fuse puller or your fingers
Most fuse boxes include a small plastic tool called a fuse puller clipped to the inside of the lid. It looks like a pair of tweezers with a slot at the end. Grip the blown fuse with the puller and pull straight out — do not wiggle or twist, as the fuse can break inside the box and become harder to remove.
If there is no puller, you can pull the fuse out with your fingers. Grip it firmly and pull straight toward you. The fuse should come free with light pressure. If it is stuck, do not force it — stop and use the puller from another vehicle or a needle-nose pliers if you have one.
Insert the new fuse of the same amperage
Hold the new fuse with the same amperage number as the one you removed. Line it up with the empty slot in the fuse box — the two metal prongs on the bottom of the fuse must slide into the two metal clips in the slot. Push the fuse straight in until it sits flush with the box or you hear a small click. Do not force it; it should slide in smoothly.
Once the fuse is seated, close the fuse box lid or door. If you removed the panel from under the dashboard, push it back into place until the clips hold it. If you opened the hood, close it gently.
Test the system to confirm the fuse is working
Turn on the car and test the system the fuse controls. If you replaced the headlight fuse, turn on the headlights. If you replaced the power window fuse, roll down a window. If you replaced the wiper fuse, turn on the wipers. The system should work normally.
If the system still does not work, the fuse may not be seated properly. Turn off the car, open the fuse box again, and check that the new fuse is pushed all the way in. If it is, the problem may be something other than the fuse — a loose wire, a bad switch, or a burned-out bulb or motor. In that case, the car needs professional diagnosis.
What to do if the fuse blows again quickly
If the same fuse blows again within a few days or a week, do not keep replacing it. A fuse that blows repeatedly means the electrical circuit is drawing too much power, usually because of a short circuit or a failing component. Replacing the fuse again will not fix the underlying problem and may damage the wiring.
Take the car to a mechanic or dealership and describe what system stopped working and how quickly the fuse blew. Bring the old fuse with you if you still have it. A technician can test the circuit and find the real cause — a corroded connection, a damaged wire, a failing motor, or a faulty switch.
Fuse types and where to find replacements
Most cars use one of two fuse types: blade fuses (small, flat, rectangular plastic cases with two metal prongs) or cartridge fuses (small cylinders with metal caps on each end). Your car's fuse box uses one type or the other. When you buy replacements, buy the same type and amperage.
You can buy fuses at any auto parts store, gas station, or big-box retailer. A pack of assorted fuses costs between three and eight dollars. Many auto parts stores will also sell you a single fuse for less than a dollar if you only need one. Keep a spare pack in your car so you have a replacement if a fuse blows while you are away from home.
Frequently Asked Questions
Can I use a fuse with higher amperage if I do not have the right one?
No. A higher amperage fuse will not blow when the circuit draws too much power, so the wiring will overheat instead. This can melt the insulation, start a fire inside the dashboard, or damage expensive components. Always use the exact amperage printed on the fuse you are replacing.
What if I cannot find the fuse box in my car?
Check your owner's manual — it has a diagram showing the location and a legend for every fuse. If you do not have the manual, search online for your car's year, make, and model plus "fuse box location". Most cars have the main fuse box under the dashboard on the driver's side, but some also have a second box under the hood or in the trunk.
Is it safe to replace a fuse myself?
Yes. The fuse box is not dangerous to touch, and you are not working with live wires. Turn off the car before you open the fuse box, and you will be safe. If you are uncomfortable doing it, any mechanic can replace a fuse in five minutes for a small fee.
Why do fuses blow in the first place?
A fuse blows when the electrical circuit draws more power than the fuse is rated for. This usually happens because a component like a motor or light is failing and drawing extra current, or because there is a short circuit where wires are touching. The fuse is designed to break and stop the flow of power before the wiring overheats.