Why Your Car Ignition Fuse Keeps Blowing?

The ignition relay is one of the most important electronic relays found on modern vehicles. It is usually located in the fuse and relay panel beneath the bonnet. It is responsible for providing power to the vehicle’s ignition system, and some of the fuel system’s components. When the key is turned to the on position, the relay is switched on and power is directed to the vehicle’s ignition and fuel system components. It is noticeable to the fuel pump and ignition coils.

When the relay fails or has an issue with the ignition fuse keeps blowing, it can cause major problems with the operation of the vehicle.

Why Does Ignition Fuse Keeps Blowing?

Usually, a bad or failing ignition relay will produce a few symptoms that can notify the driver of a potential issue.

1. Fuse Basics

Fuses come in all types and varieties, but they all work similarly. Current passes through the fuse via a small metal strip. The small metal strip creates a sort of bottleneck in the system, a point of high impedance where electricity will slow down and turn into heat. Once that strip gets hot enough, it melts and breaks the circuit connection.

For that reason to find the source of your problem, you’ll need to look for an electrical short circuit that pulls more energy through the system.

2. Multiple Circuits

The reason behind the problem with the ignition fuse keeps blowing is that multiple systems often run through the same circuit or fuse. Your ignition system might share its power source with the starter, fuel pump, fuel injectors, ignition control computer.

So, the malfunction might not even be in your ignition system, it could be a malfunction or short circuit in any of the connected systems.

3. Faults With The Ignition System

The good news is that there aren’t too many things in the ignition system itself that can blow your fuse. Because the ignition coil draws it is current directly from the battery or alternator via a relay.

If that’s the case, your fault is almost certainly in the ignition switch itself or the wires going to it. Within the distributor itself, a bad resistor can repeatedly blow fuses, but that’s unlikely unless some hack mechanic did a bad wiring job on it.

A bad coil might blow fuses, but it’ll more than likely kill the engine before that happens.

4. Ancilliary Faults

If your ignition system has a common circuit with something motorized such as a fuel pump, cooling fans, power window motor, starter, that is the source of your fault. Electric motors always draw a certain amount of wattage. Higher voltage makes the motor spin faster, more amperage causes it to produce more torque.

In the case of motor seizes up or something forces it to slow down, voltage draw will drop and amperage draw will increase to maintain the same wattage. This can easily ignition fuse keeps blowing, particularly if it’s already heavily loaded by something as power-hungry as the ignition system.

5. Faults In Wiring and Computer

Make sure you inspect the wires carefully. Because hot parts on the engine can easily burn through the wiring’s insulation. Then short the wires, and metal edges will cut through the wires and short them out.

If you’ve got fuel injection, then you might be experiencing an internal short in the computer itself. In that case, you’re out of luck because it is a junkyard for a new computer.

How To Fix The Blown Ignition Fuel?

Follow the below steps to fix the blown ignition fuel of your car. Luckily the fixing of the fuse of ignition fuel is a simple and easy process that you can do by yourself. But just you want to have basic knowledge of fuse box.

1. Unplug The Electrical Appliances

First, it is important to identify where the outage occurred. This will help you better identify which fuse is the culprit. A good way to test is to flip the light switches in each room to see which fuse has lost power.

Then, keep the lights turned off in the affected areas and unplug some of the appliances in those rooms. If you leave everything on and then restore power with a new fuse, you can run the risk of blowing it out of electric appliances.

2. Turn the Power Off

Next, you will need to turn off the main power to the fuse box. This is usually done through your electrical panel and is important for staying safe. Always try to wear safety goggles and gloves before whenever work with electricity.

3. Find The Fuse Box

Finding a fuse box, but many people may not realize where it is until a situation like this arises. In case you do not find the fuse box, follow the vehicle’s owner’s manual book to find the fuse box.

4. Identify The Broken Fuse

Then, you will need to determine which fuse has blown. These devices are made up of wires that can melt and break an electric circuit when the current exceeds a safe level. They act as a safety device to prevent an electrical fire.

Now, look for a fuse where the metal has melted or the glass covering appears foggy or discolored that’s usually the broken unit.

5. Replace The Fuse

When it’s time to replace the fuse, it’s important to find one that has the same appearance. The easiest way to do this is to take the old fuse to your local hardware store and ask for an exact replacement.

Then, it’s as easy as unscrewing the broken fuse and screwing the new one into the socket.

6. Test Your New Setup

Once everything is fixed or the problem is solved in the fuse box, turn the main power back on and make sure the circuit is working. Turn on lights and begin plugging in essential appliances, with care not to overload the circuit that was the problem.

If again the fuse blows, it might be time to look into calling a professional electrician.


While overloaded circuits are usually the cause of a blown fuse. You might want to consider asking a mechanic to upgrade your wiring if you’re continuously experiencing these problems. You can also move around plug high-energy appliances such as vacuum cleaners into other rooms so one circuit is not overworked.

An experienced electrician can help you determine what upgrades you need to meet to electrical demand of your car. Continue to brush up on proper electricity use to avoid future fuse breaks.

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