Body message
The body message is a long-running key element of the INFRA ARG, the first ever element of it that was discovered.
It's located in reserve3 and is a code written on the sheet which covers a corpse in a side building.
The body itself is likely Albert Hartman.
The code within it corresponds to keys for solving the Bunker computer code and Wasteland notes.
The Message
The code sequence written on the body is:
B1 C3 F1 B2 F2 C4 E4 G3 B2 G1 F4 B4 B2 G1 G2
Which (currently) translates to:
I will (F1(show?)) the truth (C4) to tell the right answer to the right person.
It is currently unknown what the "answer" is, but a hint suggests it is three words.
The entire body message revolves around a series of alphanumeric references, which correspond to words that have been found in INFRA maps and textures. The following is a table containing all of the current keys and their corresponding words.
| Key | Word | Source | Location | Verification |
|---|---|---|---|---|
| A | ||||
| A1 | WHAT | control_panel_003-6.vtf | reserve2 | Confirmed |
| A2 | HAPPENED | control_panel_003-6.vtf | reserve2 | Confirmed |
| A3 | TO | control_panel_003-6.vtf | reserve2 | Confirmed |
| A4 | AH | control_panel_003-6.vtf | reserve2 | Confirmed |
| B | ||||
| B1 | I | railroad_signal_control_box.vtf | reserve1 | Confirmed |
| B2 | THE | electricalbox_012.vtf | tunnel2 | Confirmed |
| B3 | IN | puzzle_box_009.vtf | tunnel4 | Confirmed |
| B4 | TO | electricalbox_012.vtf | tunnel2 | Confirmed |
| C | ||||
| C1 | IS | fuses_02.vtf | reserve1 | Confirmed |
| C2 | - | - | - | - |
| C3 | WILL | metro_control_panel_001.vtf | central | Confirmed |
| C4 | ?O??
|
S.N.W Reactor Infoboard? | reactor | Partial |
| D | ||||
| D1 | OTHER WORLD
|
Bunker Drawing | - | Unconfirmed |
| D2 | - | - | - | - |
| D3 | - | - | - | - |
| D4 | - | - | - | - |
| E | ||||
| E1 | IS | electricalbox_001.vtf | reserve1 | Confirmed |
| E2 | - | - | - | - |
| E3 | - | - | - | - |
| E4 | ?O
|
- | - | Partial |
| F | ||||
| F1 | SH??
|
- | Unconfirmed | |
| F2 | TRUTH | hallway_f2.vtf | Unused | Confirmed |
| F3 | - | - | - | - |
| F4 | ANSWER | bunker_room_005.vtf | bunker | Confirmed?* |
| G | ||||
| G1 | RIGHT | scientific_table_001_skin3.vtf | watertreatment | Confirmed |
| G2 | PERSON | scientific_table_001_skin3.vtf | watertreatment | Confirmed |
| G3 | TELL | scientific_table_001_skin3.vtf | watertreatment | Confirmed |
| G4 | - | - | - | |
| H | ||||
| H1 | - | - | - | - |
| H2 | - | - | - | - |
| H3 | - | - | - | - |
| H4 | ????E | Unconfirmed | - | Partial |
*F4 is a unique instance in which there's conflicting information on what the word should be. In reserve2, near the bird lookout spot, there is writing on the info-board about Hammer Valley birds which claims "F4 3 words", yet the bunker computer code requires it to be "answer". But as the note on the info-board is localized for different game languages, it seems likely that the information is about the answer.
Hint from Zuntti
The hint Zuntti gave us for this "code segment" is 
"BUN_BREAKER_CEN_CONTROL_VI_OFFICE_RE_SNW".
There are four clues here, each representing a location or map in INFRA.
"Bunker breaker, central control (room) (the control room in Central), Villa office, Reactor SNW (area)?"
Bunker breaker
This clue refers to the breakers outside the Bunker, in the Servicetunnel map. This has been confirmed by Zuntti's screenshot.
Possibilities here are the signs on the breakers themselves which have small text as follows:
(Breaker 1) Main text: TGD-SBC-4, small text: BR4 TGDNUM PO7 TGD1
(Breaker 2) Main text: HW-SBC-2, small text: BR4 HWNUM+1 O34 C87 EA2 N6
TGD could mean Two Gorges Dam, and HW is probably Hammer Valley Water Dam. Both breaker small texts have a "NUM" on them, prefixed by their name, with 1 being added to HWNUM.
Another possibility was the book with the bunker codes, however some codes are completely illegible and decoding with several bases does not result in anything of note.
Reading only the letters on breaker 2 reveals word "OCEAN". The breaker is assigned with number 2 so HWNUM+1 could be 3.
Comparing numbers to first letters of bunker computer yields: POR TGDU ODE COR EAU NG , which can be re-arranged into: ATOP UNDERGROU_D CORE
Central control
This clue refers to the control room in Central, where there are a few code possibilities.
Morse
The first one is the Central projector morse, which does not produce a code but a message/clue about "the right person".
Pegboard
The second one is the pegboard, which has two possibilities of its own: the pegs, the markers behind, and the unrelated notes stuck to the pegboard.
(Click this image for a HD, zoomable view.)
Pegs
These are the pegboard pegs, transcribed.
E means empty, P means peg and M means peg with marker.
MPMEEMPMPMEEEMPMPMPEEEMP PMPMPPEPEEEEEEEEMPMPMPMP (empty for 2 lines) (break) (empty for 4 lines) (break) MPMPMPEEEEMPMPEEEEMPMPMP PMPMPMPMEEEMEMPEPMPMPMPM (empty for 2 lines) (break) MPMPMPMPEEEEEEEEEEEEEEEE PMPMPMEEEEEEEEEEEEEEEEEE (empty for 2 lines) (end)
Notes
Note 1
RT 34968 BG 125675567 HK 675756 B1 = I KK 32 32123 B2 = the 1231324 123 B3 = in 364363463 B4 = TO 423424234 423 54353 C3 = 1(KKKKKKKK) = WRONG 234 OIYUIO W1I1L1L1 = RIGHT tr45 YTIT NOT B5675675567 Maybe YTWE 91267867
Removing the clutter, we can solve B1, B2, B3, B4, and C3:
B1 = I B2 = the B3 = in B4 = TO C3 = WILL
Note 2
CODE: 13523523578 YOU HAVE TO REMEMBER THAT OR YOU WILL GET SOME RANDOM STUFF I have no idea what is the stuff you know (unreadable) im out of for (unreadable)
Note 3
*
*
*
*
Ei tää mitää meinaa
E3 *
CODE *
FATAL MO(U?)TH
Villa office
See Villa woodboxes.
Reactor SNW
This clue refers to the secret SNW area of the Reactor map. The Reactor lights code is present here but does not seem to be connected to the body message, so it should be ignored.
References
- Finale has done a lot of work on uncovering this information on the ARG, see his Steam guide for the initial information.