What To Do If Car Radio Turns On Without Key?

In some cases a foul switch or switch cylinder may be the reason of car radio turns on without a key. The difficulty here is that besides the problem in the radio if once the switch is within the run or begin position, accessories become highly powered and the switch of radio never turn off.

The specific procedure for this difficulty ar completely different by looking at the creation, model, and year of your vehicle and research on schematic diagram.

Why The Car Radio Turns On Without Key?

If your car radio turns on without a key, few causes can result to such a problem. Each one plays to an application-specific situation.

1. Change The Car Battery

One of the most and common reasons for the car battery. The most popular problem is when the car refuses to work on the ACC battery. It suffers from an incompetent battery and it periodically glitches even when turned on. Your car also shows your battery notification on the dashboard, produces week highlights, and slowly cranks when you start it.

2. Head Unit

The most power wire is connected to the pinnacle unit in your car is connected to an influence supply that’s perpetually hot, the radio will not shut down ever.

If there is a head unit wiring in the car, it probably the problem from the wire. This problem is always present.

2. Ignition Switch

This ignition switch can provide accessory power to the engine even it is switched off.

There is a drawback with the ignition switch that there is a controversy between electric switch or cylinder, accent power removed when the key is removed. Check the ignition switch.

3. Key And Ignition Cylinder

Only if your car’s key or worn out ignition cylinder and you are ready to take away the key once the switch remains within the on position. This damage ignition cylinder can be in an off position, leading to the car radio turn on without a key.

4. Radio Designed To Stay On

Sometimes the radio design stays on. Even some automotive radio is on a timer. so that they are not shut off straight, off. This can lead to a problem. When these features break down, you will need help from the mechanics.

How Do You Diagnose A Car Radio Problem?

This can happen with the car such as your wire needs to be switched or replaced or you have blown fuse.

  1. First, open the car’s radio cover to investigate all the wires.
  2. Check the red and yellow cars. Both will connect with your ignition and battery.
  3. Ensure that the yellow wire is attached to the battery and red wire with ignition.
  4. If you notice the cables are not in the proper position, change them immediately or switch them back to normal.
  5. If you notice that every cable is in right place, visible sign checking.
  6. Replace the wire if you notice any damages.

How To Stop A Car Radio That Turns On By Itself?

If your car radio turns on without a key, follow this step to eliminate the problem. By following these steps you can fix the source of the problem.

1. Check The Head Unit Wire

If you face the problem from the day you have installed the head unit wire, you are facing the problem from the head unit wire only. The car radio is made up of a single ground wire and two power wires. One power wire is hot all the time and the other one will give power to the engine when running. If the power wire for your head unit is connected to a power source that is always hot. the radio won’t turn off.

You can check the wire with the voltmeter or test light. If both the power is hot all the time, you need to rewire the radio to receive the power from the source that is hot when the engine is in running position.

2. Ignition Switch

When both power wires are hot and still you do not find the power source that only hot with the ignition switch in run position or the accessories. This may be the problem because sometimes the accessories become hot after removing the key.

You have to check that whether the accessory power is available when the car turns off. You notice that power is available and realign the cylinder or replace the ignition switch as needed.

3. Ignition Cylinder and Key

This is the related problem you have seen but the problem is with the mechanical ignition cylinder not with the electronic ignition cylinder. If your key or ignition cylinder is especially worn, you may remove the car key when the switch is still in on position.

First, to deal with this problem, make sure that the ignition switch in the off position when you remove the key. This would turn off the radio.

4. Timer Radio

Check if your radio is designed for a set amount of time. Because the car radio which set on time will turn off after few minutes. This car has design in that way only.

In this case to turn off the radio, first turn off the engine, remove the key, leave the vehicle, and shut the door. After a few minutes, you will notice that the radio turns off automatically. If still, you face the same problem with the radio, check the dome light first then the door light. If the door light is turned on, you have a problem with the switch of door light.

You need some profession to check this type of problem in your car radio.


Above there we have mentioned all the issues or causes of the car radio turns on without key. After finding the cause for the radio system of your car, you can easily solve it as mentioned in this article. By following the simple steps further from preventing the issue of radio firstly replace or clean the battery, switching or replacing the switch your car wires, and by changing your car’s ignition switch.

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