What do the 28 pin connectors house?
 

So I found a link to a post for the electrical diagram.

I don't know what these acronyms stands for and I had some difficulties finding out what they are online.

https://image.ibb.co/fKDLVR/FR_S_28_Pinn.jpg

Thanks guys!

Edit:
Did more digging .. the diagram seems to be numbered
14 --- 1
28 --- 15

2 Pin = REV = Reverse
4 Pin = MACC = Microphone ACC (ignition)
5 Pin = MIN+ = Microphone +
6 Pin = SNS2 = Ground (Not sure what SNS2 stands for)
11 Pin = AGND = Aux Ground (for Aux Pins 26, 27, 28)
17 Pin = SPD = Speed Sense
18 Pin = SGND = Shield Ground (for the Mic Pins 4, 5, 19)
19 Pin = MIN- = Microphone -
25 Pin = ADPG = AUX I (Are there 2 Aux connectors?)
26 Pin = VAR+ = Aux (R) +
27 Pin = VA- = Aux (L & R) -
28 Pin = VAL+ = Aux (L) +



I have a serious suspicion that TX1+, TX-, SW1, SW2, and SWG (switch ground) are steering wheel controls .. which the FR-S does not have. But no confirmation.

Speed sensor signal, reverse switch signal, bluetooth microphone, aux in, camera video and camera power, probably some other things but those are the major ones

I was hoping if someone knew what each acronym meant .. I'd like to utilize all the relevant pins when possible ~