merlot566jka wrote:
For the OP, and I know this is a bit old, but Ill break it down...

The CCM is the master in all comms.

The CCM sends out a status update once it's woken. It checks all the players, roll call if you will. It gets a packet of data from the PCM telling all the info you get on your cluster. The data is broken down and re-routed to its appropriate places. A certain part of this is sent out on 5 wires to the cluster. This has a different type of data, made specifically for the LCD. The buttons on your DIC control control the different feeds to the LCD.

So on the 96, which uses Class 2 for its diagnostic port, there are two different serial data lines. The CCM talks on the 8192 UART line. The data is generated inside of the PCM and sent out as UART. Which is crazy, because as far as I know, there are few systems with TWO different styles of serial data. The 2004 GTO uses a module to convert the Class 2 into 8192 UART. It's called the PIM. Anyway, once the CCM gets the data it does the rest of the work.

Since the CCM is the master, and it does all of the organizing if you will, it has to be there for the rest of the systems to work.

(With a new ecm/pcm)
So how do we give the CCM what it needs? I don't know. I have an idea.

How does the EBTCM communicate with the pcm when you lose traction and it needs to retard the timing and pull the throttle shut? I don't know. Just flat out, no clue.