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How to Turn a Car Amplifier on and off Without a Remote Wire?

Installing a car amplifier can be tricky, especially if your radio does not have a remote wire. But how can you turn an amplifier on and off if you have a factory stereo with no remote wire? Let’s find out.

Generally, the easiest way to turn on the amplifier without a remote wire is to install a high-low adapter with a trigger. Also, you can run a wire from your ignition switch to the amplifier, or you can plug the wire into the cigarette lighter, but only if a cigarette lighter turns on and off with the ignition key.

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Tip: Although having a car radio initially equipped with the remote wire is the best scenario, you can still turn on and off the amplifier using a simple low-high adapter. My favorite adapter is the SCOSCHE LOC2SL, which is easy to install and equipped with a remote knob that allows adjusting the amplifier’s power level independently from the car stereo’s volume.

To understand better how simple installation is, watch the short video below:

Further down in the article, I will cover what a remote wire is and how it works. Then, understanding that, you will find out why car amplifiers need them and if they can work without one.

I will also look at other aspects of a remote wire and then give you a step-by-step tutorial on installing one.

What Is a Remote Wire, and How Does It Work?

When it comes to your car audio system, a remote wire is essentially a wire that will connect the amplifier to the stereo).

The wire will allow one piece of audio equipment to turn on and off automatically by switching the other device (your stereo or ignition) on or off. For example, if your car stereo had a remote turn-on wire connected to the amplifier, every time you turned the stereo on or off, the amplifier would turn on or off.

Typically an OEM and aftermarket stereo will have a ton of wires that come out the back of it. This will allow the stereo to connect to various elements in your car, such as your speakers, amplifier, and battery.

For the most part, all stereos now come with remote turn-on wires, and older stereos that did not come with this wire came with a power antenna wire which would achieve the same result.

Many stereos have now done away with the power antenna wire and solely have a remote turn-on wire. The concept is pretty straightforward to understand in terms of how it works.

The radio will receive power from the battery when switched on, and then the remote wire will send a signal to the amplifier to switch it on.

When the radio is turned off, a remote wire stops transferring the signal, and the amplifier turns off. You can think of a remote wire as a cut-off switch essentially.

Why Do Car Amplifiers Need a Remote Wire?

The reason that car amplifiers have a remote wire should be easy to understand. Every time you turn on your car stereo, you need to turn on your amplifier.

Without the remote wire, you would have to go wherever your amplifier is placed in your car and then turn on the amplifier. Not only would you have to turn it on every time you turn on your stereo, but you would have to turn it off every single time as well. Otherwise, it would drain the battery.

This would be not only annoying but also nearly impossible in some cases. Some amplifiers are installed behind panels, seats, and trunks of a car.

This means that many amplifiers are not accessible unless you intend to remove panels and seats from your vehicle whenever you wish to turn the amplifier on or off. The necessity of this wire speaks for itself, and it is now a crucial part of your car audio setup.

Why Does an Amplifier Stay on Without a Remote Wire?

There are many reasons why an amplifier may stay on. These include the amplifier itself, how it is wired, and also how the car stereo is wired.

Typically, an aftermarket car stereo will have three connection points concerning power. It will have a connection point for the battery, one for the ground, and then it will have a connection point for the remote wire.

Some aftermarket amplifiers even come with a remote. This is not to be confused with a remote wire, but rather it is a remote control that will allow you to turn it on and adjust certain features such as the volume or frequencies.

In some cases, when the battery wire and remote wire are incorrectly connected, the amplifier may stay on even when you turn off your stereo or car. This is because the remote wire to the amplifier may become loose, and the signal to turn the amplifier off cannot be received by the amp.

How to Turn a Car Amplifier on and off Without a Remote Wire?

Now that we know what a remote wire is and what it does, many people ask if they can indeed switch their amplifier on and off without a remote wire.

You can essentially do this if your amplifier has a remote control that allows you to turn it on and off. Then the only other instance where this is possible is if your amplifier comes with a manual on/off switch.

In any case, you will need some wire plugged either into the ignition switch or into the cigarette lighter. You can also use other connection points that work only with the ignition key turned on. Otherwise, if the amplifier stays connected to the battery non-stop with the engine turned off, it will drain it out in no time.

Can I Use Any Wire for a Remote Wire?

Typically, you will use as a remote wire a standard automotive primary wire that your car stereo and stereo harnesses come with, and this is usually 18 gauge wire. This wire type is excellent for signals but is unsuitable for high current applications such as sending power.

When it comes to powering car audio, you can’t just use any wire and, for that matter, any gauge (size) wire that you wish.

Luckily, the remote wire is just a signal wire, and you do not need to go into a lot of research about how much voltage it can carry and how much resistance it will produce to function correctly.

Can I Wire a Remote Wire to a Fuse?

You can run a remote wire to a fuse if you wish to do so. However, a remote wire does not have any fuse of its own, unlike a thick power wire for the amplifier or stereo.

Your car stereo will have a fuse located in the fuse box of your vehicle, and then your amplifier may have one or many fuses, depending on its make and model.  

You can run a remote wire to a fuse if you find that your stereo or amplifier is not functioning correctly. This will allow you to see if there is, in fact, anything wrong with that specific area of your car audio system. 

Another method is to purchase a separate fuse and insert it along the remote wire path. You can do this by cutting the wire and joining a fuse to it.

Regarding the car stereo fuse, what you would do is essentially run your remote wire to the same fuse that your radio is connected to. Although I cannot give a precise method of going about this process, I can give you a general outline of how it should be done.

You will need to remove your car stereo from the dash if you have not already.

Depending on your vehicle’s make and model, this would require the use of screwdrivers, a socket wrench, and plastic pry tools.

After you have removed the stereo, you will need to find the remote wire. The remote wire nowadays will typically be a blue/white wire.

You have to remember that all manufacturers of car audio equipment have now standardized the color of wires for car stereos because it makes adjusting and configuring the audio systems much easier.

After you have located the remote wire, you may need to lengthen it to reach the fuse box located in your car. You would extend the wire by connecting it to another piece of 18 gauge audio wire and then run it to your fuse box.

Ensure that you find the fuse for your car stereo and connect it to that and not any other fuse. You would then connect the other piece of wire from the fuse to your amplifier. 

How to Connect a Remote Wire to a Car Amplifier?

Below, I will cover all aspects of connecting a remote wire to your amplifier and connecting the wire to the stereo fuse.

Tools and Accessories You Will Need

Below are some of the tools and accessories you will need to complete this task. If you do not have these tools, there are links below to the tools I use, and I am pleased with the choice.

Take note that some tools and accessories are optional, and depending on your situation, you may need some but not all of them.

  • Screwdrivers
  • Plastic pry tool
  • Socket wrench
  • Soldering iron
  • Heat shrink
  • Butt connectors
  • Remote wire
  • Wire cutters
  • Wire strippers

How to Connect a Remote Wire to a Car Amplifier? A Step by Step Guide

When you have already installed an amplifier in the car, the next step is to connect it to the steering system. As I mentioned earlier, it can be either a stereo, an ignition switch, or any powered point in the car that is activated by the ignition key.

When you want to connect the amplifier to the stereo, the first step is to remove the stereo from the dashboard. Depending on your car’s make and model, you may need to use various tools to remove the front dashboard panel, like screwdrivers, a socket wrench, and a plastic pry tool. 

Removing the stereo will give you access to the wires, and as you already know, the remote wire will typically be blue with a white stripe.

If you would like to connect the remote wire to the car stereo fuse, I suggest adding a fuse between the amp and the wiring harness close to the stereo.

Furthermore, depending on if you have to cut any wires and extend them to a wiring harness or throughout your vehicle, you will need to cut, strip, and join them to your 18 gauge audio wire.

The best way that guarantees a stable connection is to solder them together and cover them with heat shrink. You can also use butt connectors, but since this is a remote wire, which, if faulty, can cause your battery to be drained in no time, I prefer a soldered connection.

This portion of the process is the most complicated, and once finished, all you will need to do is run your remote wire to the amplifier.

Running a wire may also take a bit of effort because depending on where your amplifier is situated, you may need to remove many more panels in your car to run the wire behind them.

The process of removing other panels in your car will not be complicated and will take the same amount of effort as removing the dash panel. I recommend running your wires under your car’s panels to maintain aesthetics and prevent it from future damage.

Once you have run the remote wire to your amplifier, the next thing you will have to do is connect it up. This step is straightforward because all amplifiers will have clear indications of where the remote wire will go.

Do take note that at this stage, your amplifier should already be connected to the battery, and the ground wire should also be in place, which means there should only be one connection point left open for the remote wire.

All you need to do is fasten the remote wire to the amplifier using a screwdriver. Some amplifiers have plug terminals, where you can just insert the wire.

Before you reinstate all the panels and anything else back in your car, check to see that the remote wire is working. Do this by turning your vehicle on and switching on the radio, and then off again.

If the remote wire is working correctly, the amplifier should turn on when you switch the radio on. If that happens, you have the correct connection, and you can reinstate all panels and other parts in your car.

The last thing to note is that you must make sure that it is set accordingly if your amplifier has a remote control.

If you require a visual aid on how to go about this process, check out the short video below.


A remote wire is a signal wire used to turn the car amplifier on and off when the stereo is turned on and off. This is an excellent feature because it would be impractical if you had to manually turn your amplifier on when you switched on the radio in your car.

Most modern amplifiers come with a remote wire connection point, and they do indeed need them to be connected for the amplifier to work correctly.

I hope that this article cleared up any confusion regarding remote wires for your car audio system. Hopefully, you were able to install it yourself.