Car speakers tend to wear out and even break over time. This is especially true of the low quality Original Equipment (OE) found on most cars and trucks. Internal components can wear or loosen with regular use, and there’s nothing you can do about it.
That being said, car speakers tend to fail one at a time. Every speaker in a car audio system dying at the same time is very unlikely without some major abuse such as turning up the volume just enough to loudspeakers went out . When all the speakers in the car audio system stop working at once, the problem is usually in the head unit amplifier or wiring .
In some cases, a wiring problem between the head unit and one speaker can even cause all speakers in the entire car audio system to turn off at the same time.
In order to narrow down the exact cause of this type of car audio system, a few basic issues need to be addressed.
Head Unit and Amplifier Exclusion
If your head unit turns on just fine, but you’re not getting any sound from the speakers, it’s easy to conclude that the problem is with the speakers. However, just because the head unit is on does not mean that it is working properly. Before doing anything else, you want to:
Make sure the head unit has not entered anti-theft mode, which requires a car radio code.
Check your volume, fade, and pan settings.
Check the various audio inputs (eg radio, CD player, auxiliary input, etc.).
Check any onboard fuses.
Check for loose or disconnected wires.
If you cannot find any issues with your head unit, you will need to determine if you have external amplifier . In car audio systems that use external amplifiers (both OEM and aftermarket), the amplifier is the most common cause of this type of problem because the sound has to travel through it on its way to the speakers. As you test your amplifier, you’ll want to:
Make sure the amplifier is actually turned on.
Determine if the amplifier has entered «protect mode».
Inspect for loose or disconnected input or output speaker wires.
Check both the built-in and on-board fuses.
While there are many common problems with car amplifiers that you can identify and fix on your own, you may find yourself in a situation where the amplifier looks fine even if it has failed. In this case, you may just need to bypass the amplifier to make sure the head unit and speakers are working, at which point you can get by with your head unit’s internal amplifier or install a new aftermarket amplifier.
Car Speaker Wiring Check
When you checked the gain and pan settings on your head unit, you may have found that they were set to the speaker or speakers that failed, and that you were able to get sound by going to the speaker or speakers that were working. In this case, you’re looking at a car stereo wiring problem, or a faulty speaker or speakers.
Because speaker wires are often routed behind panels and moldings, under seats, and under carpet, they can be difficult to visually inspect. Depending on your situation, it may be easier to check for continuity between one end of each wire (on the head unit or amplifier) and the other end on each speaker. If you don’t see continuity, that means a wire is broken somewhere. On the other hand, if you see ground continuity, then you are dealing with a shorted wire.
If your speakers are installed in doors, then a common point of failure is when the speaker wire runs between the door and the door frame. Although door wiring harnesses are usually protected by hard rubber sheaths, the wires can still break over time due to the repetitive stresses that come from opening and closing doors. With that in mind, you can also check for continuity and shorts with open and closed doors. If you find that one speaker is shorted to ground in this way, it may cause all speakers to turn off.
Car speaker testing
Another way to test speakers and rule out bad wiring at the same time is to get some speaker wire and just run new temporary wires to each speaker. Because it’s only temporary, you’ll have to access the speakers by removing door panels, trim, and other components, but you won’t actually have to run new wires properly.
If the speakers work with new wires, it’s safe to assume that the old wiring is the problem, in which case routing the new wires will solve the problem.
You can also «check» automotive speakers by disconnecting the wiring harness from the head unit or amplifier and touching in turn the positive and negative wires of each speaker to the positive and negative terminals of the 1.5V battery.
If the speaker wires are not broken and the speaker is not completely broken, you will hear a small click when you touch the wires to the battery terminals. However, the fact that you can take the «loudspeaker» out of a speaker with a 1.5V battery does not necessarily mean that the speaker is in good working order.
If you end up deciding everything else and you do run into random failure, then it’s time to just en masse replace car speakers . However, you probably need to make sure they haven’t been blown up by someone turning on the stereo.