My boss has a C5 and challenged me with reverse engineering and repairing his EBCM. I would like to compare his broken one to some others and see what I can find. I have searched Craigslist and eBay but I cannot find any broken ones at a reasonable price to play around with. I do like to tinker and learn but not when it is prohibitively expensive. If anyone knows of a source for broken modules or wishes to donate theirs to my cause, please let me know. I would rather practice on a separate unit before I permanently ruin my bosses even more than it is.

 

Oh great, no year or option.


Mr. Sam

 

Pre or post 2000.... There are many on the Forum that are "toast"

 

His is a 2000 with the M version.

I would like to get my hands on as many different units as possible to get schematics of the PCB's. This will also help in finding the root cause of the problems. I haven't even seen a module yet but if the modules are coil driven I have a hunch that the failure is due to either heat, back EMF or current spike from the field collapsing. Either way it will get me some brownie points with my boss and probably a few people on here that don't want to pay something crazy for a used module.

 

I have heard that 99 percent of the ECBM problems are that they are not used very often and become sticky. You need to activate it once in awhile by slaming on the brakes to enguage the abs controls within, does this sound correct ???

 

I have not yet seen the mechanics of the system but that does make some sense. If the oil just sits but the actuators and never circulates it could gel into a sludge with enough heating and cooling cycles.

Something like that sounds like it would be an easy fix with a soak in some acetone. I have looked at some online pictures but I have to hold one and really see how it works to understand it.

I should have the 2000 M version in a day or two when he pulls the unit out.

I personally am not far enough into my career to have a vette yet, but when I do it will be a 74 Stingray T-Top like my uncle once had. I do electro-mechanical systems every day. I don't want to mess with them on my cars as well.

 

Question What codes did he have? It may or may not be the ebcm

Entering On-Board Diagnostics
To enter the Diagnostic Display function perform the following steps:
1. Turn ON the ignition switch, with the engine OFF.
2. Press the RESET button to acknowledge any warning messages present.
3. Press the OPTIONS button on the Driver Information Center (DIC) and hold.
4. While holding the OPTIONS button press the FUEL button 4 times within a 5 second period.
5. System will first enter automatic display mode followed by the manual display mode.
Automatic Display DTC Mode
The automatic display feature allows you to read each module DTC display function in an automatic
display sequence. Each system module DTC will be displayed for 3 seconds followed by a 1 second pause
before the next DTC is displayed in an automatic sequence. If no DTC information is available from the
system currently displayed on the DIC, the DIC will display NO CODES for that system. If there is a
communications problem between any systems, the IPC will display NO COMM when the DIC is trying to
communicate with that system. When all DTCs have been displayed for all systems, the IDIC will display
NO MORE CODES for 2 seconds before entering the manual mode. At any time during the automatic
display function, the manual display feature can be activated by pressing any button on the DIC except the
E/M button. The E/M button is used to completely exit the DIAGNOSTICS mode at any time.


Manual Display DTC Mode
The manual display feature allows you to manually select each module DTC display function. The manual
mode will automatically be entered after the automatic DTC display sequence is complete, or can be
entered at any time during the automatic mode by pressing any button on the DIC except the E/M (E/M
button is used to exit the DIAGNOSTIC mode at any time). When the manual mode is selected, the IPC will
display the MANUAL DIAGNOSTICS mode message for 2 seconds, or until any button on the DIC except
the E/M is pressed. After the MANUAL DIAGNOSTICS mode message is displayed, the IPC will display
the first system abbreviation and quantity of codes stored for that system, then the IPC will wait for further
instructions. The buttons on the DIC provide the following functions when operating the on-board
diagnostic feature in the manual mode:
DIC Button Function When In Manual Mode
1. FUEL Previous DTC
2. GAGES Next DTC
3. TRIP Previous System
4. OPTIONS Next System
5. E/M Exit Diagnostics
6. RESET Clear DTCs

 

I will forward this information and reply back tomorrow.

 

Good luck on finding the fix for these. If you can, you will be a HERO, and have plenty of work. How will you test them?

 

Error Coded that he has logged:
C1226 C1255 C1243

Google Tells me:
28-TCS - Traction Control System
C1226 LF Excessive Wheel Speed Variation
C1243 BPMV Pump Motor Stalled
C1255 EBTCM Internal Malfunction

He also told me that the contacts were cleaned and that did not help. He is pretty sure that the control board or the module is cooked.

 

Tinkering keeps me out of the bars and keeps my mind sharp. I would have to learn the circuits and duplicate it before I could find a way to test it. It might even have to be tested on car. I am not sure how it works or what would be involved yet.

 

I for one am pulling for you. Good Luck and keep us informed of your progress.

 

not sure if this helps but perhaps worth considering
http://www.corvettesolution.com/blog...ce-c5-corvette

 

I will gladly pay shipping for a couple of pre 2001 units. If some of you have confirmed broken ones. I would like to start getting the potting off as it sounds like this is going to take some time. Luckily I have done this before and even with epoxy potting so it can be done.

 

If it is a solder joint issue I would prefer to make a clone board and solder it with SnPb solder. This would pretty much be a permanent fix. The switch to lead free solder has caused many many devices to fail like mentioned. Xboxes PS3's PS4's Laptops, ect all failures due to lead free solder.

 

I never thought about the fact that there were "mechanicals" in that module - going to find a safe place and lock 'em up

 

Good luck finding a way to fix the pre-01 EBCMs. You would make a lot of people happy if you can do it.

 

Do the 01-04 EBCMs fail regularly too but they're just easier to fix?

 

Wayne read thru this
http://forums.corvetteforum.com/c5-t...43-1255-a.html

Pay particular attention to post #15 which talks about the sub codes of the C1255. You may need someone with a Tech II to be able to break out the subcodes. This will give you a better idea if the problem is repairable or if you need to start looking for a used EBCM.

That is from 8VETTE7

I would also Start checking grounds and see if the unit is getting proper voltage

 

From what I read it has to do with the way the PCB is potted (aka sealed in gunk). Potting has its own flaws. Sometimes the potting becomes conductive over time as it breaks down over time and heat. This is a common problem in Klipsch audio amplifiers. The potting shorts out the components and blows the switching mosfets. I have seen this at work with some types of potting as well. Potting is also terrible for heat transfer. It could be a thermal failure of one of the components.

If potting and solder joints are the issue, my approach would be to clone the PCB upgrade and flaws and then just do a transplant.

Wishful thinking at this point. But not impossible.