Corvette CCM Reverse Engineering Anyone?

[spfautsch]

The three solder pads on the bottom-left appear curious to me.

Those are all tied together - there's another trace between the right pads on the back side. Holding a light behind the unpainted area around the pads it seems like there might be a trace leaving the right pad in a middle layer, but it dead ends on the visible layers. It reads 40mohm to ground.

This is just the normal self-diagnostic pin on the ALDL connector (on a 94-96, this is pin 12, which you then jumper to pin 4, ground).

I figured that's what it was but haven't been able to look at all the schematics thus far.

Why would you care about the vin that is programmed.

I'm interested in knowing if the remanned unit has had the eeprom erased before I connect it to the car. Since I know my vin and how many miles are on mine I'm hoping to be able to extrapolate their location in the dump. Though I'm somewhat worried they used some sort of hash algo on the odometer reading. Edit: and it occurred to me it's probably not stored in units of miles but rather some proprietary GM unit.

Edit: Still no luck with serial data. May have to put it back in the car to troubleshoot.

[-=Jeff=-]

Setup my bench to read a couple CCMs. but I keep getting the Bus is too Noisy.. I have not changed anything on my setup. Suggestions on what to check?

EDIT:
1990-1991 works but 1992-1993 keeps giving the Bus to Noisy, then is says it cannot find the Heartbeat. I have another port setup and running YAT to read the data, the CCM seems to be sending the commands as expected, but for some odd reason, the Arduino setup to fake the messages is not working. As I thought having the reply messages will help. I also tried driect connection to CCM, (No ECM present)

[-=Jeff=-]

After reading through the post and fixing some Arduino code, I got it working. I need to improve my bench setup and clean the wiring up

[In-Tech]

Hiya,
What was the secret find? Serial?

[-=Jeff=-]

I need to have the ECM inplace and connected to the be able to read out of the CCM correctly..