I own a 2000 toyota tundra, everything is stock and today i bought the JL amp, JLsub, wires off Craigslist then bought that little box that convert the speaker wires to RCA ( it was a 50 watt converter box thing ) I did it my self since I've installed a couple already and they worked just fine but for some reason this one doesn't want to work, the amp light is showing i got the rca cables hooked up to the input of amp and have both sides of the back speakers ( they were white wires one with black strip ) hook up to that little converter box, i read about 5v from the speaker wires but when i try looking for volts on the rca side and get nothing, i get about 3v at the sub, what am i doing wrong?

Check the gain settings on the amp. Is there a variable output control on the Line Output Converter? Is one coil of the sub wired out of phase?

I got it, their was a switch on the amp to switch between hp and lp i think but i switch that and it worked

You definitely want low pass.

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