Many people who take their 1997-2004 Corvettes to track days have reported that the Electronic Brake Control Module (EBCM) has virtually locked out the brakes at one time or another. Apparently the way to trigger it is to press the brake pedal abruptly with grippy tires. GM claims there's no such thing, but it's been described by so many people that I assume it's a bug that just never cropped up during their testing. I want to find it and fix it before it finds me, and jvaldez wants to fix it before it finds him a second time.
There are two versions of the EBCM that were used in Corvettes, with the changover happening at or around the 2000 model year (I don't know exactly). So we might have to do this twice. Hopefully the second iteration will go faster than the first.
My car is a 2002 but a local shop gave me a defective EBCM from a 1998 to play with, and I'm happy to try to figure that one out. The tricky thing about that one is that I can't get it apart. As far as I can tell, the case was filled with epoxy and the circuit board was mashed into it component-side down, so none of the components are visible, and it's going to be impossible to pull the PCB out in one piece because it's anchored to the case by this epoxy.
Does anyone have ideas about how to open this thing up? Are there any products that might be able to dissolve or weak the epoxy without destroying the electronics?
And, does anyone have a later-style EBCM that they can take apart and study? I'd rather not take apart my C5 so I'm going to order one off ebay but it will take a while to get here.
Plan of attack, more or less:
1) identify the components, especially the CPU
2) get the datasheet for the CPU
3) look for a way to read the firmware using BDM or JTAG or similar, to get a head start on reverse engineering
4) try to sniff a firmware upgrade session using a Tech2 or equivalent
5) use info from 3 and 4 to create EBCM Hammer.
I'm told that GM was fond of 68HC11 chips in that era, so maybe that's what we'll find?
