1) I have turned the subwoofer off from the HeadUnit. Now if I remove the sub from the car and if +ve/-ve of the sub speaker cable touch each other, nothing would happen....rite?
mani, i have already answered this question of yours . like others said, just tape them.
2) The subwoofer speaker cable has no identification marks on it so I don't know which part is +ve and which is -ve. I have removed the sub from the car at the moment. Now when connecting it back, how do I find out which strand of speaker wire is +ve and which one is -ve? Or it does not matters?
you can check this by using a AA cell. connect each strand of wire to each end of the cell.
the sub will either move outwards, or go inwards. for correct polarity, just do the following:
From a website:
Using a 1.5 volt battery (any size), touch the positive terminal of the battery to the positive wire going to the speaker, then do the same for the negative wire. Have a friend look at the speaker. If the speaker pops out, the polarity is correct. If the speaker pops in, the speaker is hooked up backwards (out of phase). To fix this, simply reverse the wires when hooking the speaker back to the amplifier. A word of caution here: DO NOT hold the battery power to the speaker for more than 1 second, all you want to do is to see if it pops in or out. You will damage the speaker if you hold constant power to it. Do not use a higher voltage. Also, do not try this test on tweeters, you could fry the voice coils. If there are crossovers with capacitors along the line, this test will not work (capacitors block DC voltage). Bypass the caps momentarily.
//youtu.be/http://www.youtube.com/watch?v=aP_4-r4Hk-o
