What is an AM2 fuse? (explained)

In the vehicle, the AM2 fuse is a fuse that is part of the ignition system. It is one of these parts of the ignition system that cooperates together and activates the engine when the owner puts it into the ignition and turns it. 

If there’s an issue with the AM2 fuse, the owner may have to try several times to turn the engine off and on. This type of thing is relatively cheap, so it will not be expensive to ask a mechanic to replace it.

What does an AM2 fuse meaning?

When a vehicle is designed perfectly, there’s no reason for the manufacturer to change it. You’d be surprised at how many vehicles are exactly the same when you strip away all their paneling, carpets, and padding. 

But once the manufacturer has the perfect vehicle design and layout, only a complete and total revamp and new vehicle line would make them change their best manufacturing method.

For the past two decades, many vehicle manufacturers have been using the new AM2 fuse in their vehicles’ ignition. But what is the AM2 Fuse and why is it so important?

The AM2 fuse is a part of the ignition. This part switches the gate to engage the starter.

When a driver goes to turn on their vehicle’s ignition, the turning motion must activate the AM2 circuit and draw power from that circuit or fuse. It must do this for the ignition to start the power.

What are common problems that involve the AM2 fuse?

First, since the AM2 fuse controls the ignition switch, you cannot start your vehicle if the fuse has been damaged or is no longer in the right position. But that doesn’t always mean if there is an issue with the ignition, then it must be a problem with the AM2 fuse.

In order to find common problems with the AM2 fuse, we should look towards the ignition switch, as the fuse directly controls it.

Here are three common issues that involve the ignition switch:

The steering wheel is locked and cannot become unlocked. Many vehicles now have a steering wheel lock so that robbers and your crazy Aunt Shelly cannot drive away with your vehicle, even if they break open the window.

But sometimes, the steering wheel can stay locked. When a lobstering wheel is stuck, it means that the ignition cylinder has become stuck and the steering wheel locks and will not loosen.

A stuck steering wheel has a simple solution. Just grab the steering wheel with both of your hands in the ten and two positions and rock it back and forth until the steering wheel unbinds and unlocks.

The immobilizer is not detecting the right key code. In the last 10 years, many cars and trucks, and SUVs do not require the driver to put the key in the ignition.

Having the key close to the ignition is all it needs to start the vehicle. These vehicles have buttons that start the vehicle.

Inside of the vehicle key that has a specific code for your vehicle. A sensor in your car checks for this code every time the button is pressed.

So, what if you have your keys as close to the button as possible, but the button won’t become unlocked and start the vehicle?

This is usually because of a broken immobilizer antenna wiring. The antenna is the part that can detect the key code coming from the FOB key.

To fix this issue, you have to take your vehicle to a certified mechanic. They’ll be able to make sure the key has the right code and fix the antenna so it can detect the code.

The AM2 fuse keeps blowing. Depending on the location of the fuse, you’ll probably be able to change the fuse out yourself. However, if you noticed that you keep replacing the AM2 fuse, then there is a bigger issue at hand.

It is not common for an ignition switch fuse to blow, but the fuse problem is usually due to a faulty resistor. A resistor is a small component that helps regulate the electrical current passing through a fuse.

So, when a fuse blows regularly, the resistor is not doing this job and regulating the current. The resistor needs to be changed. The wiring that provides an electric current to the resistor and the fuse will need to be taken out and replaced as well.

Cost of an AM2 fuse and other parts

An AM2 fuse isn’t a special type of fuse, so it is not expensive to replace. However, if your vehicle is on the other side, then it may be harder to find the AM2 fuse for your vehicle.

This only pertains to vehicles that are 15 years old and older. The average cost of an AM2 fuse will cost less than $15 for a pack of three.

The actual cost comes from the labor replacing the fuse. Opening up the steering wheel and replacing the fuse can cost up to $60.

In some cases, you’ll have to replace the entire ignition switch. Replacing it is a costly repair job and the part alone can cost up to $300. The labor cost of replacing the ignition switch can be up to $180.


The AM2 fuse is a common fuse in many vehicles. This helps control the electrical current that powers the ignition switch. Without the AM2 fuse, a driver cannot turn on the ignition and turn on their engine.

If the AM2 fuse blows, then it needs to be replaced. Two common signs of a malfunctioning AM2 fuse are the immobilizer not picking up the key code and the steering wheel staying locked. If the AM2 fuse blows regularly, then the electrical current is too powerful, and the resistor is probably broken as well.

  • Eric Williams

    I'm the founder of Daily Car Tips. I wrote articles in the automotive industry for more than 10 years, published in USA and Europe. I love sharing my knowledge and insights with fellow enthusiasts. Join me on this journey as we explore the exciting world of cars together!

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