What is this harness / cable for?
 

Hello people.
I need your help on this one:

1987 Mazda RX-7 FC S4 N/A, 5 Speed manual, Sport package trim level.

I don't know what this harness is (the one with the green connector), and I don't know what it is for.

Attachment 692109

I've searched for it on the FSM, but I've found nothing. The only thing the FSM talks about are the relays that are next to it.

Whatever it is, it's not originally supposed to run through the battery air duct.
Does it only have one wire on the connector?

It has 12 wires!

Attachment 692105

Having just redone my entire front harness I was intrigued because I don't remember anything that looks like that.
I just scanned through the FSM electrical section (all I have is for S5 though) and couldn't find a single connector that was laid out like that one.
Good luck.

i have never seen that connector on any of the 15-20 FC's i have owned

After following all of the wires one by one (it took me an hour or so...) I've found what this harness was...
When I bought this car, it came with an aftermarket alarm (from make SONAR) which was already deactivated (wires cut, no remote control for it, no key for the electronic central).
This harness is one of the components left from that alarm. All of the wires were cut except for 2 green ones, which were still connected to the turn signal lights, and 1 yellow which was soldered to the ignition position of the car key.
I've removed it from the car.

Thank you for your help :)

I was going to say that Nothing runs through that hose as it is a Breathe tube for the battery.,and that wire is not stock...but of course I am too late..(no soup for me!)

Thanks anyway misterstyx69. You have always been helpful :)