Car Stereos: Connecting Sub with no output on Head Unit, rcas, still havent

Question
Hi, i recently bought a new headunit but discovered it doesnt have a direct Sub output RCA but it had RCA connections labelled Right and Left didnt mention if output or input but when i got it installed i showed the technician and he wired it up but couldnt test if it worked. now my amp appears not to be getting power but all the wiring is fine. Can these RCAs actually work? and have i damaged my amp at all?. Still havent checked the two fuses on the amp itself but could this be the problem? as the wires from amp to sub might have connected causing a short and blown the fuses?
Any help would be great! and thank you for your time

Answer
Hi Taylor,

Generally, hooking up RCA wires in the wrong order or direction won't damage anything, it just won't work.

If the amp isn't getting any power, then I'd suggest the wiring probably isn't fine.

You're going to need a multimeter to verify there's 12V between the amp's ground and power, as well as 12V between the amp's remote and ground when the deck is on.

Justin