B-bodies are same as F-body, the main difference is, there is much more idle traffic sent from PCM.
B and F has digital traction control. All request are handled through aldl communication.
Traction request spark retard by sending aldl frame and frequency signal at pin a23 to PCM

Y-body traction is an analog system with simple on off request. Pcm [pin a12] sends pwm signal for TPS % to traction. Traction request Spark retard from PCM by grounding pin c12
PCM hadles the spark retard only.

Y-bodies are completely different. Pcm has zero idle traffic. All the idle traffic is sent from ccm. PCM only responds to ccm request.
[F0 56 F1 C9] ccm send aldl broadcast message with F1 id
[10 59 08 4F 02 00 3E ] this is some mistery frame send from ccm probably to module with $10 ID
[40 57 FF FF 6B ] CCM send mode 7 request to PCM
[41 67 02 F2 00 4F 4E 01 00 46 1A C3 88 00 42 FF FF 00 A0 A0 9B ] PCM answer to CCM

You can see what is in the frame here
RESERVED:F343 fdb off_F371 ; UNKNOWN MODE 07 MSG 07 COMMMAND
RESERVED:F345 fcb $40 ; @ ; ALDL INSTUMENT PANEL 2 Y
RESERVED:F346 fcb $41 ; A
RESERVED:F347 fcb $80 ; À
RESERVED:F348 fcb $12
RESERVED:F349 fdb $1992
RESERVED:F34B fdb $1992
RESERVED:F34D fdb byte_156 ; UNKNOWN MODE ??? memory
RESERVED:F34F fdb byte_108
RESERVED:F351 fdb byte_176
RESERVED:F353 fdb word_1A2
RESERVED:F355 fdb byte_256
RESERVED:F357 fdb byte_9E
RESERVED:F359 fdb byte_9F
RESERVED:F35B fdb byte_182D
RESERVED:F35D fdb word_182B
RESERVED:F35F fdb word_182B+1
RESERVED:F361 fdb unk_3B00
RESERVED:F363 fdb byte_19D
RESERVED:F365 fdb word_1BD
RESERVED:F367 fdb word_1983
RESERVED:F369 fdb word_1983+1
RESERVED:F36B fdb word_1B16 ; ADR #7 AD filtered ?? TRANSM TEMP
RESERVED:F36D fcb 0
RESERVED:F36E fcb 0
RESERVED:F36F fcb 0
RESERVED:F370 fcb 0




to see what idle traffic is send by PCM check this cal data
This is from F-body cal

RESERVED:3AC7 fdb off_F253 ; MODE 7 IDLE TRAFFIC LOAD 16 pointers
RESERVED:3AC9 fdb 0
RESERVED:3ACB fdb 0
RESERVED:3ACD fdb 0
RESERVED:3ACF fdb off_F2B7 ; TRACTION ALDL MODE
RESERVED:3AD1 fdb 0
RESERVED:3AD3 fdb 0
RESERVED:3AD5 fdb 0
RESERVED:3AD7 fdb off_F2CB
RESERVED:3AD9 fdb 0
RESERVED:3ADB fdb 0
RESERVED:3ADD fdb 0
RESERVED:3ADF fdb off_F2B7 ; TRACTION ALDL MODE
RESERVED:3AE1 fdb 0
RESERVED:3AE3 fdb 0
RESERVED:3AE5 fdb 0


On y-body is all zeroed and there is no idle traffic from PCM
On b-body the data sent is much more.

I also have some request for you guys to patch eehack raw module.
When I try to send empty message it adds some extra byte.
I want to send [Id address] [message lenght] [checksum] with no data byte.