How to install a car stereo without a wiring harness? [EXPLAINED]

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I have always wondered how to install a car stereo without a wiring harness because I didn’t think they were as important as now I realize they are. If the wires are harnessed, that means they are not exposed to humidity, vibrations, dampness, and abrasions, but that doesn’t mean they are protected from all of that. But, what do we need to install a car stereo if we don’t have a wiring harness? Which wire is for what? Do the colors mean anything?

What do we need to know about the wires?

Obviously, before starting to install anything, we have to understand what is each piece for, in our case, the cables. In our case, the harness adapter has different color wires and each of them has a different function.

What are the power wires responsible for?

They are responsible for powering up our car stereo. The colors of its wires are red, black, and yellow. The first one is really important, as it will be the one that helps us when turning the radio on and off. The second one is basic because our car stereo won’t work if it’s missing. The last one helps the battery remain stable, also, it has constant power.

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Is the antenna involved?

Yes, it is, and it also has a wire, in this case is blue. It’s necessary to control de signal and power antenna for our radio.

There are two types of wires we can encounter. The first one is plain blue, used for the AM or FM frequencies, while the second one is blue with white stripes and collects both frequencies and CDs, Bluetooth, and media.

What about the speakers?

Its wires are really easy to find, as they come in pairs. The first wire has stripes and is for negative wires, and the second one doesn’t have stripes and, as logical, is for the positive wires. Then we have the white cables, these are for the front left speakers. For the front right, they are grey. For rear left, green. And for rear right, purple.

What has the brightness anything to do with how to install a car stereo without a wiring harness?

Finally, we’ll find our stereo has two wires left, both are orange. One of them increases the brightness, and the other lowers it. Depending on the car you have, you may not find these cables, as your car doesn’t have them installed.

5 steps we must follow to install the car stereo securely

  1. As with every electrical thing we need to work on, the first thing to do is cut the power. How? Really ease, just remove the key from the ignition. You can also do it disconnecting the battery. This will prevent you from being electrocuted.
  2. Moreover, to make sure the insulation is correct, we need to tear off the wire insulation by removing it of every wire of the radio and vehicle.
  3. Once we’ve separated the insulation, we need to start wiring again. In this step we need to be sure which type of car we have, as there are two options:
  4. The first type has similar wires as the radio desk, the car will also come with no harness. In your case, connecting the wire is really easy, you just have to attach the wire color to color. When you’re done, you need to grab your harness adapter and solder and heat shrink it. This way you’ll have the best connection.
  5. The second type has only one wire with two heads: one positive and one negative. Don’t match them by colors but by pairs. The red goes with the yellow, the black with the blue and the other already have a pair. When you’re done, just match the positive and the negative.

Now what?

Now you’re almost done! Just connect the stereo harness to the stereo and check if everything works. Don’t forget the speakers. If everything goes smoothly, turn off the car again and put everything back where it belongs.

Hey, there mobile audio lovers! My name is Vincent Talbot, founder and chief editor at 99carstereo.com. Ask any mobile audio fanatic, installer, or company rep what makes a good car speaker, sub, or amp, or, better yet, why he or she prefers a certain brand over another, and be prepared to endure a litany of opinions, viewpoints, and passion-fueled perspectives. To be honest, mobile audio shopping can be a daunting task without a guide, so I’ve assembled what I feel are the best products to consider to make things easier for you. More.

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Mobile audio is my passion, so before I put anything in front of you I exhaustively research a broad range of products, review all the available information on them and ultimately make a curated list of recommendations. As a result, I want this site to be a trusted resource that you can rely on and that is not rigged by brand sponsorship, so you can use this information when you are planning your new mobile audio upgrade.