jensen tube dual voice coil subs

My neighbor gave me 2 Jensen tube subwoofers. They look like this:

I want to put them in my Nephew's car. I hooked them up and they don't  sound bad, nothing spectacular but good enough for him. Does anyone know the exact specifications for this sub. Also, they are dual 4 ohm voice coil. On one of the subs one of the voice coils is not working. Can this be fixed?? Tested?? is it something I can do myself?? lastly; if the voice coil can't be fixed, is there any reason why I can't run them as single 4 ohm voice coils? If I can them I can wire them parallel for a 2 ohm load.

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2005 Honda Accord DX

You can use only one coil per subwoofer, this will just cut the rated power of the subwoofer in half,  You are correct about them being able to run at 2ohms if you only use 2 coils, if you use all 4 coils you will either be running at 4 or 1 ohm..  As far as fixing them it is possible a wire may have came loose in the tube itself..   Check this, if everything is connected you will have to measure the resistance on the coil that isnet working if it is durastically different than 4 ohms thaen you probably have a fried coil..   I cant seem to find the specifications for the subwoofer and tube.  Are there any model numbers on the tubes?  theses might be helpful