How to Test a Two Wire Audio Circuit
- 1). Turn off your audio equipment and remove any batteries from the appliance you are inspecting. Make sure that all electrical sources are removed.
- 2). Open up your speakers and look for the electrical contacts for the speaker magnets. These should be a metallic color or look like soldered points.
- 3). Touch your ohmmeter across these points. You should get a reading. If your reading is infinite, it means that the speaker has failed electrically and it should be replaced. Also inspect the paper cross section of the speaker for cracks. This will produce lower quality sound when played. Failed speakers are replaced for a modest fee.
- 4). Inspect the wire leads coming into the speaker's wires. Locate the electrical connectors for each speaker. These points originate the current fed to the speakers. They will look like soldered points.
- 5). Place the ohmmeter across these points. Verify you get a reading. If your reading is infinite, there is no output to the speakers and the audio output is damaged at the source. A major replacement is required.
Source...