Could be the amp is blown but again you said the amp is on. So it could be the sub. I would try a door speaker and set the amp settings to low and see if you get sound..
Could be the sub or amp just got to test them both out.
97"Ford Ranger 2.3L
Mods: Headlights 8k HIDs, Green Fogs HIDs, FlowMaster 40 Series, Tails lights, Shaved Tail gate,Roll pan, 5/6 lowered, Ibeams, 2in coils, Flip kit, Honda Metallic Paint
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