Typically you have to install a bypass that tricks the head unit into thinking the emergency brake is engaged (or with AT you might have to trick it into thinking it's in Park). These are pretty easy to find for aftermarket stereos. But I'm not sure if it's possible or how easy it would be for a stock radio.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |