HELP anyone know where this plugs into?

[21M3SR]

I recently had my 22 m3p in for service to replace the subwoofer enclosure. After previous poor service from my local service center I wanted to make sure it was good but when I pulled the trunk liner back I noticed this plug by the amplifier and I can’t seem to find where it goes. Would someone be able to check where it’s plugged in on their car? I’d take it to the dealer but they are far away….. and usually break more then they fix

 

[Soul Surfer]

Flux capacitor coupling?

 

[Watts_Up]

Can you check the voltage of each wire?
Does the harness belong from the amplifier or from the car body?

 

[21M3SR]

I can tomorrow. It belongs to the car body and it runs under the amplifier assembly

 

[21M3SR]

It comes out of that loom you can see in the bottom of the photo