Car Radio Accessory Wire (ACC) Not Working [CAUSES & FIXES]

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What are the possible causes of the accessory wire not working?

Radio Accessory Wire (ACC) allows you to access your radio even when the ignition is turned off. If your car stereo only works when the ignition is turned on, it’s very likely that there is something wrong with your ACC. There could be issues in the vehicle wiring, the battery, the fuse of the radio, or the ignition switch itself.

To fully comprehend why your car radio experiences issues such as working only when the ignition is turned on, you must first learn more about your vehicle’s ACC position. ACC is an abbreviation for accessories, and it refers to your vehicle’s convenient, electrical parts such as backlights, the radio, headlights, windows, cigarette lighter, the air ventilator, and power seats.

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The Accessory Wire (ACC) for the radio allows you to listen to the radio even when your car is switched off. If it does not happen, then there is probably something wrong with your Radio Accessory Wire (ACC).

There are several issues that can arise with the radio ACC. In this post, I will go through the most common causes for Accessory Wire (ACC) not working and provide the relevant fixes for them.

What Causes the Radio Accessory Wire (ACC) To Not Work And How to Fix Them?

There are several possible reasons why your Accessory Wire (ACC) is not working. The following are the most common causes and the fixes for them.

Wiring Issues

A wiring issue is a common cause of a car radio refusing to work while in the ACC position. This could indicate that your wires have been switched, that you need to change your wires, or that you have a blown fuse.

The yellow and red wires are the most important of all the wires connected to the radio of your car. The yellow wire should be connected to the battery so that your radio receives power when you turn on the ignition. At the same time, attach the red wire to the ignition’s ACC so you can utilize your radio even when the ignition is turned off.

If your wiring is correct, you may need to change the wires themselves if they are damaged. You may also need to replace your fuses if they were the source of the problem with your car radio.

Bad Battery

If your battery is no longer good, your radio will most likely only work when the ignition is turned on. You can fix the problem by charging the battery if it has been discharged, cleaning the terminals, or simply changing it.

Faulty Ignition

Since your ignition switch is faulty, your car radio may only function with the ignition turned on. This could be due to general wear and tear. If your radio cannot properly attach to the ACC, it will not switch on. When you have difficulty twisting your key or when an accessory malfunctions, you have a faulty ignition switch.

If your radio isn’t functioning in the ACC position due to a faulty ignition switch, you should replace your car’s ignition cylinder.

Can I use a different wire instead of the ACC wire to power my car stereo?

No, you should never use a different wire instead of the ACC wire to power your car stereo. The ACC wire is designed to supply power to the stereo, and using a different wire may cause damage to the stereo or the car’s electrical system.

How do I test the ACC wire in my car?

The best way is with a multimeter. Set the multimeter to the DC voltage setting, then connect the black lead to a ground point in your car and the red lead to the ACC wire. Turn the ignition key to the “accessory” position, and the multimeter should read a voltage between 10 and 14 volts.

Can I connect multiple wires to the ACC wire in my car?

No, you should not connect multiple wires to the ACC wire in your car. The ACC wire is designed to supply power to the car stereo, and connecting multiple wires to it may cause damage to the stereo or the car’s electrical system.

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