4 ohm Speakers measuring 0.5 ohms before crossover? What?

[Jezzey 10+ year member]

I recently installed a new (everything) system. Everything is working "great" excepect that I wasn't hearing sound from the woofer of my front components (4 ohm). Every couple minutes when the volume was turned up I would hear them pop on, garble distortion, then my amp would throw itself into protection mode. I tested the two channels that I knew were working on the amp and verified that the problem was the speakers/wiring/installation, not the amplifier. I took out my multimeter (I might add that I'm not great with a multimeter, but tested things several times to generate a consistant measurement). I unplugged the speaker wires from the amps and began to test resistance: (I will refer to components as a speaker unless otherwise specified) The 2 speakers that were working measured 4.0 ohms. The two speakers that were not working measured 1.4 ohms... Phase two of testing: with the amp unplugged I measured resistence of the input terminals on the crossovers: 0.8 ohms (something is wrong) I unplugged the tweeters and woofers from the crossover and measured their resistance: Tweeters 3.8 ohms Woofers: 0.4 ohms. There is about 18 inches of wire between the speaker and the crossover. Wiring is straight forward, no bridges, nothing run in parallel. Any ideas what the problem could be? Google can't help me. If no one has any ideas, I guess my next test will be to remove the door panels and the woofer portion of the component to measure resistance at the terminal.

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[supereikenator 10+ year member]

I think that means they are blown.

 

[Jezzey 10+ year member]

Thank you for the fast reply. It is possible, however they are new speakers and can handle more than the amp can push. I think I may have it figured out. An issue unique to my car that could be causing the terminal to be contacting part of the metal on the door (i.e shorting out).

 

[Jepalan]

Thank you for the fast reply. It is possible, however they are new speakers and can handle more than the amp can push. I think I may have it figured out. An issue unique to my car that could be causing the terminal to be contacting part of the metal on the door (i.e shorting out).

This happened to me in a Honda install I did a few years ago. Try measuring resistance (ohms) between each speaker wire and chassis ground. If you read anything other than infinity then your terminals are shorted to chassis.

 

[Jezzey 10+ year member]

oh that is way easier than what I was going to do.