How to Test Car Speaker Wire Polarity with Multimeter [STEPS + VIDEO]

Testing the speaker wire with multimeter yields accurate results, eliminating the need for guesswork in determining the state of the wire. As someone who tweaks around their car’s speakers a lot, this information is invaluable.

STEP 1. Disconnect the Speaker

Removing a few strands of wiring or unfastening certain clamps is typically all that is required to disconnect a speaker.

Larger components, such as panels, may need to be removed, although this is dependent on how your car’s audio system is configured.

The thing you are looking at here are the speaker wires that were connected to your car speakers.

STEP 2. Turn On Car Radio

Switch ON the car’s head unit and turn up the sound so the voltage increases.

STEP 3. Set the Multimeter

On your multimeter, set the small DC Voltage preset (200m).

STEP 4. Touch the wires with the Probe

Touch the red probe of the multimeter to one wire and, the black probe to the other wire.

Now watch the value. If the vale stays positive, the red probe is on the positive wire and the black probe is on the negative wire.

If you reverse the probes you should see the negative value which means that the polarity is mixed up.

STEP 5. Compare All Speaker Results

Repeat for each speaker, then compare the results to see how they’re doing. It’s important to keep in mind that certain vehicles have two sets of positive and negative wires running into each speaker.

Each probe should be attached to a positive and negative wire independently in this situation.

STEP 6. Replace Any Faulty Parts

Replace any defective parts and revel in their volume. If there is inadequate continuity between all terminals, the problem is most likely with the speaker or the speaker wiring.

If these tests do not address your problem, you should replace both.

Check out this video explenation