I see you're new - Welcome!
But you should only post your question in one forum only (or ask the moderator to move it)
Can you post a pic of your trunk so we can seethe "black box"
Normally the OEM set-up has a speaker assembly in each door, which contains a speaker and an individual amplifier for that component; there is also an assembly in the passenger footwell which contains an amplifier that drives a speaker in the same assembly, plus an additional speaker between the seats.
If there is an amplifier in the trunk, it is non-standard & means your system has been modified - there's no telling what may have been done without further invstigation and info.
I would think it rare that there would be absolutely zero sound if all the OEM components were in place & wired-up - usually failures are associated with wailing, hissing or popping - it would be extreme to have all three amps fail with a resultant zero output. (but not unusual to have all three amps fail!)