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Why are Car Radio RCA Outputs Not Working?

If your car audio system isn’t sounding as good as you’d like it to, the problem may not be your speakers or amplifier. Instead, there may be an issue with small RCA outputs that send the signal from the radio to the amplifier.

But why do RCA outputs in car stereos may not work, and more importantly, how can you fix it? Let’s find out.

Generally, the most common reasons for RCA outputs not working are:

  • The RCA cables are not properly connected
  • The RCA cables are damaged
  • There is an issue with the car stereo’s internal amplifier

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Tip: When you demand the sounds from the speakers to be of the highest quality, there is not only a radio or the speakers that play a critical role in the overall performance.

Essential are also the wires, and you do not want to compromise the overall system’s output by using low-quality cables.

The best RCA signal wires that I can recommend are KnuKonceptz Klarity. They are not only great but also much cheaper than most competitors.

KnuKonceptz Klarity RCA Cable 2 Channel RCA Interconnect 16 Feet (5 Meter)

In the article below, I will explain these reasons in detail and provide tips on getting more value out of your RCA cables.

Why Car Stereo RCA Outputs May Not Work?

If your car audio system isn’t sounding as good as you’d like it to, the problem can be caused by damaged or not correctly connected RCA outputs.

It may seem ridiculous that such small connectors can cause such pain, but yes.

This is because RCA are designed to transfer signals, and any damage, no matter how small, can disrupt that signal and cause sound quality issues.

In some cases, the RCA outputs may not work at all, while in others, they may produce crackling or static noise depending on the damage.

Fortunately, in most cases, the problem is relatively easy to fix by yourself.

What Is the Car Stereo RCA Output?

The car stereo RCA output is a set of jacks that allow you to connect your car stereo to an external amplifier or other audio components.

The RCA outputs usually consist of two jacks, one for the left channel and one for the right channel. There are however, some stereos that have four or even six RCA outputs for multichannel amplifiers.

RCA outputs are typically used to connect a subwoofer to a car stereo, but you can also use them to connect other audio components such as an Equalizer or a Sound Processor.

AudioControl DM-608 6 by 8 Channel Matrix Digital Signal Processor

When connecting an external amplifier or other audio components to your car stereo, high-quality RCA cables are essential to avoid sound quality issues.

How to Fix Car Stereo RCA Outputs?

There are several ways to go about this, but the most important thing is to check if the RCA cables are correctly connected and undamaged. If they are, check the car stereo’s internal amplifier.

Check if the RCA Cables Are Correctly Connected.

The first thing you need to do is make sure that the RCA cables are properly connected.

To do this, first disconnect the RCA cables from the car stereo and then reconnect them, making sure that they are inserted all the way.

If you’re using an aftermarket car stereo, also make sure that the RCA cables are plugged into the correct output (usually labeled “subwoofer” or “sub-out”).

Pioneer CD Digital Music Player - Old Model

Check if the RCA cables are damaged.

Even if the RCA cables are correctly connected, they may be damaged, which can cause sound quality issues.

To check if the RCA cables are damaged, disconnect them from the car stereo and inspect them for any physical damage such as cuts, fraying, or breaks in the insulation.

If you do not see the visual damage, the next test you have to do is use a multimeter.

Set the multimeter to ohms mode and then touch one of the probes to each end of the RCA cable. If the multimeter beeps or shows a reading close to zero, this means that the RCA cable is shorted and needs to be replaced.

Check the car stereo’s internal amplifier.

If the RCA cables are properly connected and undamaged, the actual problem may be with the car stereo’s internal amplifier.

To check if the amplifier is working, you’ll need to use a test light or a multimeter.

First, disconnect the RCA cables from the car stereo and then touch one of the probes of the test light or multimeter to the ground wire, and the second probe to the RCA’s positive wire.

If the test light lights up or the multimeter shows a reading close to 12 volts, the amplifier is working, and the problem is most likely with the RCA cables.

However, if the test light doesn’t light up or the multimeter shows a reading close to zero, the amplifier is not receiving any power. Therefore, you may need to take the stereo to the professional for further testing.

Keep in mind that if you have an external amplifier, its RCA ports also need to be checked.

How do I test my RCA radio output?

Testing signal output from the RCA is different from testing the RCA wires, but you should do it each time you investigate the connections in the stereo.

A few steps below show the test of the actual quality of the sound being produced.

1)Turn on the car stereo and turn the volume up to about halfway.

2)Connect one end of the RCA cable to the “Subwoofer Output” or “Preamp Output” jack on the back of the stereo.

3)Touch the other end of the positive (red) RCA cable to the positive terminal of your multimeter, then touch the negative (black) RCA cable to the negative terminal of your multimeter.

4)Set your multimeter to “DC Voltage” mode and observe the reading. It should be between 11 and 16 volts. If it’s not, then there’s a problem with your car stereo’s output, and you’ll need to investigate it further.

5)Now disconnect the RCA cables from the stereo and set your multimeter to “Ohms” mode.

6)Touch one of the probes to the positive (red) terminal of the RCA cable, then touch the other probe to the negative (black) terminal of the RCA cable. You should see a reading close to zero ohms. If you don’t, there’s a problem with your RCA cables, and they need to be replaced.

7)Next, connect the RCA cables back to the stereo and set your multimeter to “AC Voltage” mode.

8)Touch one of the probes to the positive (red) terminal of the RCA cable, then touch the other probe to the negative (black) terminal of the RCA cable. You should see a reading between 11 and 16 volts.

Conclusion

Although it is an annoying experience, having problems with the RCA outputs does not have to be the end of the world.

By following the steps above, you can quickly locate and fix the problem.

If you’re having trouble with your car stereo’s RCA outputs, there are a few things you can do to try to fix the problem quickly.

  • First, check the RCA cables for any physical damage.
  • Next, check the car stereo’s RCA outputs with a multimeter to see if they provide the proper voltage.

If the RCA cables are damaged or the car stereo’s output is not working properly, you’ll need to take the stereo to a professional for further testing.