Why Do Motorcycle Fuses Blow?

Fuses are the safety components attached to various electrical systems of your motorcycles and prevent them from damaging. The fluctuating and over-current supply can directly damage the circuit board of the specific system, which is costly to repair.

Why Do Motorcycle Fuses Blow? Motorcycle fuses blow out due to overloading, loose connections, current drawing accessories, mixing of wires, use of incorrectly rated fuses, and corroded connections. It is also due to the addition of aftermarket accessories, bad batteries, and damaged insulated coating of wires.

The primary symptom of a blown-out fuse is shut down of their respective component. It stops the current supply, and different parts of motorcycles stop working.

Causes Solutions
Overloading Avoid attaching heavy equipment
Loose connections Avoid frequent off-roading
Current drawing accessories Inspect the starter gear, ignition coil, and switch
Mixing of two wires Check amperage with multimeters
Use of incorrectly rated fuse Check fuse amperage for replacement
Corroded wiring connections Use electric contact spray cleaners
Aftermarket accessories Check the power of aftermarket accessories
Bad batteries Regular inspection of batteries
Damaged wires insulation layer Use electric tape as a temporary solution


Overloading of circuits leads to blown-out motorcycle fuses and prevents them from damage because of their costly repairs. The issue comes when the current moving through the wires exceeds their limited range.

The circuits are designed for specific current voltage, and these can burn out when the power supply increases. In addition, the old wires cause the overloading of circuits because these cannot hold the excessive supply of current.

Moreover, the issue also comes due to short circuits, wear and tear in electric wires, and their misalignment. The current cannot move in an even wire when the electric systems are faulty.

In addition, the issue comes when you use the motorcycle to jump-start other vehicles that need excessive power. The circuits are not designed for these high-power drawing automobiles, which leads to damage.

Check the electric wires to inspect their connections and proper grounding. Avoid connecting heavy equipment with them because their wires and circuits are not designed for them.

Loose connections

The loose wiring connections cause a blown-out fuse of your motorcycle. The heat from the loose wiring connections travels to these parts and causes the problem.

The issue also comes when loosely connected wires come in direct exposure to the motorcycle’s frame and anything touching the ground.

The loose wiring connections disturb the electric current flow, damaging the circuits. The loose connection issue comes when you continuously drive on off-ramps with several jumps and jerks.

The continuous jiggling and vibrations from the road affect the wiring connections and make them poorly connected. Avoid driving on off-ramps for longer because it can cause damage.

Moreover, it is necessary to maintain its components when you take your motorbike off-roading frequently.

Current drawing accessories

The electric circuits are connected to various electrical components of the motorcycles and have a separate fuse for their normal functioning.

The problem in the respective component causes the excessive drawing of electric current from the circuits and leads to a blown-out fuse.

The stuck starter gear and faulty ignition coil, fuel injection system, ignition switch, and fuel pump need more current to function, making the system faulty.

You can fix it by inspecting the connected components and their functioning. For example, check the ignition switch and starter relay when you hear the clicking and uneven sounds from them while using these components.

Mixing of two wires

The mixing of electric wires and crossing over issue comes when two cables of different systems come in contact with each other and increase the resultant amperage.

The fuses of sensors blow out when other wires mix with them and supply current that the system cannot hold.

The crossing-over issue occurs when two wires near the engine melt and fuse. Use the multimeter to check the amperage on the specific components that are continuously causing the issue is necessary.

The high amperage of current than their proper value shows the crossing of wires. Therefore, it is better to call the mechanic to separate their connection and reinstall it.

Use of incorrectly rated fuse

Motorcycle fuses of different ratings are available, such as 5A, 10A, 15A, and 20A. The different ratings represent their current passing range according to their connected components.

Often, the use of wrong-rated types for electric components causes this problem. The issue comes when you do not check the amperage of the old fuse and purchase the new one with a different ampere.

Using less ampere for heavy equipment cause blows out when more current with excessive heat passes through them.

Check the amperage of the old ones when you replace them with new ones. You cannot replace or mix the fuses of the starter and headlights because of their different current drawing capacity.

Corroded wiring connections

The corrosion leads to a blown-out fuse because of resistance in the current flow and eventually overheating. Rust in electric connections starts to build because of poor maintenance and regular inspection.

The moisture can seep into the connectors and circuit boards and affect their wirings. Corrosion can make the connections faulty and cause the brittleness of wires.

These become fragile and break easily when you move on off ramps. In addition, rust causes the deterioration of wires and produces short circuits in them.

Proper inspection of electric connections in a routine is necessary to prevent wires from moisture attack.

Shut off the power supply to deal with corroded wires and remove the rust. Use the electric contact cleaner sprays and treat the affected area with them.

Wipe off the spray and rust with a dry cloth and reconnect with the power supply.

Aftermarket accessories

People face the blown-out fuse of the motorcycle and hindrances in the functioning of their respective electric components.

Many people leave the exposed copper wire on the ending side to attach the aftermarket components to enhance its appearance and make them luxurious and comfortable to use.

The addition of aftermarket accessories like a sound system draws an excessive amount of current, damages the insulated wires’ insulated layer, and produces short circuits.

The frayed wiring and short circuits lead to a blown-out fuse. The issue also comes when you attach the aftermarket headlights to your motorbikes to make them attractive and stylish.

Avoid adding aftermarket accessories that draw excessive power from the power source. I always check the power of the accessories while adding them to my vehicles.

Bad batteries

Bad and damaged batteries disrupt the smooth flow of electric current, and eventually, the motorcycle fuses blow out.

The batteries power the electric components by converting chemical energy into electric energy. The faulty battery causes a high current supply to the circuit boards, and you can face the problem.

The issue comes from overcharging the batteries, which store too much charge. In addition, you can face this because of loose and corroded terminals of the batteries.

Inspect and maintain the batteries of your vehicles for its maintenance. Clean the corroded terminals and check leakages that can cause rust in terminals.

Tighten the loose terminals of the batteries by cutting off the electric supply.

Damaged wires insulation layer

Plastic insulation is present in electric wires to make them safe and reduce the risk of harmful situations. These plastic coatings are cheap and good insulators and protect from electric shocks.

It does not allow the current to flow outside because of its high resistance against heat and current. The problem comes when the insulation layer gets damaged and allows the copper wires to come in contact with metal parts.

The insulation layer is made of plastic material, which can melt due to age and excessively high temperatures. Moreover, short circuits and damaged wirings produce heat and increase the risk of their damage.

The current from these copper wires move unevenly into the different metal part and cause the fuse to blow out. Wrap the exposed copper wire with electrical tape, but it is not a long-term solution.

These can also melt because of high temperatures and cause issues.

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