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How To Fix a Car Radio That Only Works With Ignition On

You don’t know why, but your car radio only works with the ignition on. You don’t want to bring it to a mechanic unless you can’t really help it, so you decided to scour the internet for answers. What causes a car radio to work only when your car is on the ignition, and how can you fix it?

To fix a car radio that only works with the ignition, you must first understand what the problem is, and in many cases, it can be a battery or wiring problem. If it’s the former, you may need to replace your battery. If it’s the latter, you may need to switch your wirings or replace your ignition switch.

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In this article, we will discuss why a car radio may only work when the ignition is on. It will also help you diagnose the car radio’s potential problems and tell you how to solve them.

What Does the Car’s ACC Position Do?

You need to know more about your car’s ACC position to fully understand why your car radio experiences problems like working only when the ignition is on. ACC stands for accessories, and it’s connected to your car’s convenient, electric-powered components, such as the radio, windows, power seats, cigarette lighter, headlights, backlights, and even the air ventilator. 

ACC allows current to pass through your accessories for them to power up and function. This means that even when your ignition is off, you can access your car’s basic functions.

You can listen to the radio or roll your windows up or down. You can also switch your lights on and off, and many other things.

car stereo works only with ignition on

So, when your car radio only works with the ignition on, it’s highly likely that something related to your ACC needs attention. This could be your car’s wirings, your battery, radio fuse, or the ignition switch itself. 

If your wirings trouble your car radio, you may have one of the following issues:

  • Incorrect wire placement
  • Damaged Wires
  • Blown Fuses

On the other hand, if your car radio suffers from battery issues, you may possess a weak battery that can’t produce the required voltage to power your radio. Lastly, a worn-out or faulty ignition switch may affect your car as well.

Why a Car Radio Only Works With Ignition on and How To Fix It

A car radio, like any other electrical device, needs the power to run. Hence, it draws electric currents from your car’s battery. If your car’s battery power isn’t sufficient or the wirings meant to instruct your car about energy-drawing get mixed up, you’ll have problems. Similarly, a faulty ignition switch may also cause your radio to refuse to work when you’re in the ACC position.

This section will explain why a car radio only works with the ignition on, show you how to confirm your diagnosis, and tell you how to fix each issue. However, remember that if you are unsure about anything, it’s best to contact a professional.

If you don’t have the equipment needed for doing basic car tests yet, check out AstroAI Digital Multimeter, on Amazon.

Change Your Car’s Battery

One of the main reasons a car refuses to work on ACC is a weak battery. You’ll know your car radio suffers from an incompetent battery if it periodically glitches even when turned on. Your car will also show you a battery notification on the dashboard, produce weak headlights, and slowly crank when you start it.

However, the most accurate way to figure out if your car battery is causing your radio malfunction is to follow the steps below.

  1. Switch your headlights on for two minutes.
  2. Prepare your multimeter by setting it to a measurement above 15 volts.
  3. Connect the positive lead and negative lead to their respective slots.
  4. You can do that by plugging red to red and black to black.
  5. You should see a result of at least 12.6 volts.
  6. Keep the multimeter attached to your car’s battery.
  7. Turn on the Ignition.
  8. The result should not drop below 10 volts.
  9. You need to clean your battery or replace it if the result drops below 10 volts.

If you prefer watching video tutorials, visit Chris Fix’s clear and detailed clip about testing a car battery with a multimeter:

How To Fix a Car Radio With Battery Problems

As mentioned earlier, you need a properly working car battery to have a functioning radio. So, if your battery isn’t good anymore, your radio will likely only work with the ignition on. You can fix your car battery by recharging it if it’s been drained, cleaning its terminals, or replacing it. 

To recharge your car battery, check out this lively YouTube clip from Scotty Kilmer:

Meanwhile, cleaning your battery’s terminals only requires some sandpaper and WD-40, so it should be easy enough without a tutorial. However, you can check out Chris Fix’s video from above to see that, too.

Lastly, to replace your car battery, watch Scotty Kilmer’s YouTube tutorial:

Switch Your Wires or Replace Them

The next reason that causes a car radio to refuse to work while you’re in the ACC position is a wiring problem. This could mean your wires got switched, you need to replace your wires, or you have a blown fuse.

Diagnosing this issue is relatively easy when you follow all the steps:

  1. Open your car radio’s covers so that its wires are exposed.
  2. Check for a yellow and red wire that connects from your radio to your ignition and battery.
  3. You need to ensure the yellow wire is connected to the battery and the red wire is attached to the ignition.
  4. If the cables are not in their proper positions, simply switch them back to normal.
  5. If all cables are in their right places, check for visible signs of wire damage.
  6. Replace the wires if you notice any damages.
  7. You should also check the fuses connected to your radio to see if they need any replacements.

How To Fix a Car Radio With Wire Problems

As mentioned earlier, among all the wires attached to your car radio, the yellow and red wires are crucial. The yellow wire should connect to the battery so that your radio draws power when your ignition is on. Meanwhile, the red wire should connect to the Ignition’s ACC so that you can use your radio even when the ignition is off.

On the other hand, if your wirings are correct, you may need to replace the wires themselves if you notice any damages to them. You may also need to change your fuses if they’re the ones that caused your car radio’s issue.

Replace Your Car’s Ignition Switch

Your car radio may also only work with the ignition on because your ignition switch is faulty. This may occur from normal wear and tear. If your radio can’t connect to the ACC properly, it will not turn on. You’ll know your ignition switch is faulty when you find it hard to twist your key or when you experience an accessory malfunction.

How To Fix a Car Radio With an Ignition Switch Problem

You need to replace your cylinder if your radio isn’t working on the ACC position because of your ignition switch. To do this, check out another YouTube tutorial from Scotty Kilmer. It’s a cheery but helpful clip about replacing the ignition switch of a car:

Final Thoughts

Three things typically cause a car radio to work only with the ignition on. Once you have diagnosed which one of those caused your radio problem, you can then solve it. You can fix your radio issue by replacing or cleaning your battery, switching or replacing your wires, or changing your ignition switch.