Sounds like an aftermarket install. If the previous owner left all the components and they are still hooked up, then possibly. Chances are it's just leftover parts they didn't bother to remove and is disconnected.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |