How to Determine the Positive and Negative Poles of a Speaker

[StJayce]

When the speaker cone retracts inward, the terminal connected to the positive pole of the battery is the negative pole of the speaker, and vice versa. Set the multimeter to the ohm range, then touch the two terminals of the speaker with the probes. The speaker will move slightly when contacted, and pushing forward indicates the standard positive and negative poles. Generally, for audio output wires, the wires for the same speaker will be of the same color group. The positive wire will be solid-colored, while the negative wire will have thin black lines or dashed lines.

[VonAlex]

I've been repairing cars for years, and determining the positive and negative terminals of a horn is actually quite straightforward. The horn has two wires: the positive is the power supply wire, and the negative is the ground wire connected to the car body. If you want to be precise, use a multimeter: place the black probe on a metal part of the car body as the ground, and touch the red probe to the wire end. If it shows a voltage (usually around 12 volts), that's the positive; if it shows nothing, it's the negative. No professional tools? Try a small bulb tester: connect it to the power source, and the wire that lights up the bulb is the positive. Or use trial and error: connect directly to the battery—if the horn sounds, the connection is correct; if not, swap the wires and try again. Remember to turn off the engine and disconnect the power before working to avoid short circuits or fires. This is important because reversing the polarity can burn out the horn's internal coil, leading to weak sound or no sound at all. On older cars, the wire ends may be faded, so beginners should start with basic tests.

[MatteoDella]

I've figured out the polarity when DIY installing speakers. Speakers have two wires, right? The positive is usually the power wire from the switch, with a brighter color; the negative is the ground or black wire. To measure, touch the black probe of the multimeter to the metal part of the car frame and the red probe to the wire end—a positive reading indicates the positive pole. No tools? Try this simple test: connect to power, and if the speaker sounds, it's correct; if not, swap the wires and try again. But be cautious—don't touch randomly to avoid sparks. Why be careful? Reverse connection can distort the sound or damage the speaker internally. When modifying speakers, ensure the negative is reliably grounded for stable output. It's recommended to clean the wire ends before starting—rust can affect performance.

[TeaganAnn]

When helping someone repair a horn, I found that identifying the positive and negative terminals isn't difficult. The horn has two wires: the positive wire connects to the power source, while the negative wire is grounded. You can use a voltmeter to test: place the black probe on a metal part of the car body and touch the red probe to the wire—if the voltage shows a positive number, it's the positive terminal. Alternatively, connect directly to the battery: if the horn sounds, the polarity is correct. Remember to turn off the power first to avoid safety risks. Reversing the connection can damage the horn.