Why Did My Car Speakers Stop Working?

car door speaker
Car door speakers often fail due to the speaker wires breaking. Car Culture Collection / GettyImages

Question: Why did my car speakers suddenly stop working?

My car stereo has always worked well enough, but the other day I got in and the speakers had stopped working. The stereo still turns on, so I assume it’s a problem with the speakers. It seems weird for all of them to stop working at once, though. What could have caused my car speakers to suddenly stop working?

Answer:

While car speakers do tend to wear out, and even break, over time, it’s somewhat unlikely that every speaker in your car audio system chose the same day to kick the bucket.

If your speakers aren’t working (e.g., there is no sound coming from them at all), the problem is more likely in the head unit or possibly in the amp. In some cases, an issue with the wiring between the head unit and a single speaker can cause all of them to cut out, as well. In order to narrow down the exact cause of your problem, you’ll have to do a little troubleshooting.

Ruling Out the Head Unit and Amplifier

If your head unit turns on just fine, but you don’t get any sound from the speakers, it’s easy to jump to the conclusion that the speakers are the problem. However, the fact that the head unit is turning on doesn’t mean it’s working properly. Before you do anything else, you’ll want to:

  1. Verify that the head unit hasn’t entered an anti-theft mode that requires a car radio code.
  2. Check the volume, fade and pan settings.
  3. Test different audio inputs (i.e. radio, CD player, auxiliary input, etc).
  1. Test any onboard fuses.
  2. Check for loose or unplugged wires.

If you are unable to locate any issues with the head unit, then you will want to determine whether or not you have an external amplifier. In car audio systems that use external amps (both OEM and aftermarket), the amp is the most common cause of this type of problem, since the audio has to pass through it on the way to the speakers.

In the process of checking out the amp, you will want to:

  1. Verify that the amplifier is actually turning on.
  2. Determine whether or not the amp has gone into “protect mode.”
  3. Inspect for loose or disconnected input or output speaker wires.
  4. Test both inline and onboard fuses.

Although there are many common car amplifier problems that you can identify and fix on your own, you may run into a situation where the amp seems fine even though it has failed. In that case, you may need to simply bypass the amplifier to verify that both the head unit and speakers are working, at which point you can either get by with your head unit’s internal amp or install a new aftermarket amp.

Checking Car Speaker Wiring

When you checked the fade and pan settings on your head unit, you may have discovered that they were set to a speaker or speakers that had failed, and that you were able to get sound by moving to a speaker or speakers that work. In that case, you’re looking at a problem with your car stereo wiring or a faulty speaker or speakers.

Since speaker wires are often routed behind panels and molding, under seats, and beneath carpet, it can be difficult to visibly inspect them. Depending on your situation, it may be easier to check for continuity between one end of each wire (at the head unit or amp) and the other end at each speaker.

If you don’t see continuity, that means the wire is broken somewhere. On the other hand, if you see continuity to ground, then you’re dealing with a shorted wire.

If your speakers are mounted in doors, then a common point of failure is where the speaker wire passes between the door and the door frame. Although door wiring harnesses are typically protected by hard rubber sheathes, the wires can still end up breaking over time due to the repeated stresses endured in opening and closing the doors. With that in mind, you may also want to check for continuity and shorts with the doors both open and closes.

If you find that one speaker is shorted to ground in that manner, that can actually cause all of the speakers to cut out.

Testing Car Speakers

Another way to test the speakers, and to rule out bad wiring at the same time, is to obtain some speaker wire and to simply run new, temporary wires to each speaker. Since this is only temporary, you will have to gain access to the speakers by removing door panels, trim, and other components, but you won’t actually have to route the new wires properly. If the speakers work with the new wires, however, it’s a safe bet that your problem is with the old wiring, in which case routing new wires will fix the problem.

You can also “test” car speakers by unplugging the wiring harness from the head unit or amp and touching the positive and negative wires of each speaker, in turn, to the positive and negative terminals of a 1.5V battery. If the speaker wires aren’t broken, and the speaker hasn’t totally failed, you will hear a slight pop when you touch the wires to the battery terminals. However, the fact that you can get a “pop” out of a speaker with a 1.5V battery doesn’t necessarily mean the speaker is in good working order.

If you end up ruling everything else out, and you really are dealing with a coincidental failure, then it's time to just replace your car speakers en masse. However, you should probably make sure that they weren't blown out by someone cranking up the stereo. This may also be a good time to think about upgrading your car stereo as a whole, although selecting some good aftermarket speakers to replace the blown factory units can actually help a lot by itself.