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Things To Do When Head Unit RCA Output Not Working Properly

Once you connect your RCA cables to the right ports of your car stereo and amplifier, it would work just fine and provide excellent sound, right? Unfortunately, sometimes your head unit's RCA output just doesn't work even though your setup is perfect.

So, what to do if head unit RCA output not working? Of course, you need to identify the root of this problem first. It can be worn-out RCA cables, faulty sockets, wrong input, internal damage, or muted sub-level. To solve the RCA output issue, you need to ensure the right RCA cable setup with functional wires and sockets.

Let's dive deeper into the reasons why there's no RCA output on your car stereo and find out some easy fixes.

If you want clear and improved sound from your stereo speakers, the head unit RCA output must function optimally. Otherwise, your amplifier won't enhance the low-level sound quality and the speakers might not play anything at all.

So, here are the possible reasons, identifying processes, and fixes for no RCA output head unit issue.

Reason 1: You Might Have Muted the Sub-Level

Before going into more complicated reasons, let's start with a simpler issue that most people don't consider. Nowadays, most aftermarket stereos allow you to control the output through the RCA cables to the amplifier.

If you have somehow muted the sub-level from your car stereo, your speakers won't be able to play any bass or sound. That might be the reason why there's no RCA output on your stereo.

How to Identify

To solve this, check out the settings on your stereo. You might have unknowingly turned down the sub-level to the lowest level which eventually stops playing the bass.

Possible Fixes

If the sub-levels are muted or too low, turn them up to a decent level so that the amplifier receives a good amount of signal from the stereo.

Reason 2: Wrong Pairing of RCA Cables

To connect the amplifier to your stereo, you need to pair up the RCA cables with the right sockets. It's easy to mess things up if you have no previous experience hooking up RCA outputs. So, putting the wrong cable in the wrong socket is another common reason why your head unit isn't providing any RCA output.

How to Identify

Here, you have two options: separating all the cables to check the pairing and using a multimeter to test the socket feed. We recommend going for the first option as it doesn't require any devices.

You need to refer to the owner's manual of the stereo or amplifier to find out which cable goes into what socket. This will help you to easily know if you have messed up the socket connection.

check the RCA pairing using a multimeter

Possible Fixes

On the back of your stereo, you'll find a wiring harness where the RCA cables are connected. You'll see two RCA cables are connected to the 'Sub-Out' or 'Audio Out' section. Take them off and reinstall them correctly.

Typically, the RCA cables are red and white which go into the red and white sockets of the stereo and amplifier. However, you should always check out the wiring diagram to know exactly where the cables need to be connected.

Reason 3: Pinched or Worn-Out RCA Cables

Sometimes excessive pulling and fiddling of the RCA cables causes them to tear. Also, the sockets and wires are often pinched if the placement of the stereo was wrong.

In that case, the wires that send signals from the stereo to the amp fail to function properly. Therefore, your head unit will send poor RCA output or no output at all.

How to Identify

First of all, you must visually inspect the cables to check if the insulation has worn out somewhere. If there are no signs of damage, the problem might be internal.

In this case, you can use a knife to cut off the insulation and expose the inner wires. Most RCA cables have a white and black wire inside the insulation. If you notice any of them has come loose from the socket, this might be the culprit.

Another way is to use a multimeter to check out signal continuity. For this, set the multimeter pin to the continuity option and turn on your stereo speakers. Put the multimeter probe on the tip of the RCA socket and check for voltage change.

Again, place the probe on the outer ring or shield of the socket. If you notice voltage changes, the cables are completely fine. Otherwise, there might be a loose or pinched wire somewhere inside the insulation.

Possible Fixes

The RCA wires might be repairable, but we recommend going for new ones as RCA cables are pretty cheap. You can visit your local hardware shop to purchase new RCA cables and connect them to get high-quality output from your head unit.

Reason 4: Is Your Stereo or Amplifier Functional?

So, there's no issue with your RCA cables or head unit settings. Now what? There might be some internal damage to your amplifier or car stereo.

Damaged internal circuits, resistors, or diodes can block the head unit from sending proper signals through the RCA cables.

How to Identify

Unfortunately, you need to expose the internal parts of the stereo and amplifier to identify where exactly the damage is. Don't try this yourself if you don't have any experience working with such devices.

Stereo or Amplifier Functional

Possible Fixes

Take your devices to an expert to repair them. The process is very complicated and any wrong step can further damage the device. So, you should either repair them with the help of a professional or replace them with new ones.

Wrapping Up!

So, now you know how to solve head unit RCA output not working issue. Here, the key is to identify which related parts are affecting the head unit and RCA cable's performance.

After that, you can easily solve the issue by following our detailed guide. Don't hesitate to take help from a professional if you fail to find the real cause.

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