I need help! My subwoofer isn't working and the rear speakers are very low!

Hi. The subwoofer in my car isn't producing any sound and the rear speakers
are really low, even when I've adjusted the sound to be rear only. When I
google my car's make and model and troubleshooting, it keeps referring me
to info about the FX35. I can't seem to find anything relating to my car's
system. I checked the subwoofer and all wires are connected as they should
be so was going to check the amp but I can't locate it. I was told it's in the
trunk on the right side but there isn't any door or indication something is
behind the carpet. I don't want to ruin it by pulling it out if there's not even an
amp in there. Please advise, anyone with knowledge about this. Thank you!