Vibe cbr1 subwoofer

Question

i have just installed a second hand vibe cbr10 subwoofer with built in amp i believe i have wired it up properly, but there is still no sign of power as the light does not come on at all i dont know whether it is that the actual sub doesnt work or whether i have wired it up incorrectly but i have th cable attatched from the positive terminal on the battery to the positive terminal on the sub/amp and the cable from the other terminal on the sub/amp attatched to an earth point, i have the cable connected from the back of my jvc stereo to the input terminals on the sub/amp and also the wire connected from the am cable from my stereo to the middle termina on the sub/amp could you help me please?