lionelhutz

There have been a few threads about how the early EBTCM module and the 99-00 SWPS are not available.

There were a few comments about updating the EBTCM to the later model but they generally get shot down with comments that it wouldn't be possible without major re-wiring work, basically replacing everything electrical in the car.

Well, I finally got my service CD installed again and took a look at the schematics for the EBTCM wiring on a 98 and a 04. The systems are very similar. I found a spot where they were referred to as a version 5 and version 5.3 which indicates it's not a complete new design but rather a revision on the first design. All the wiring is the same wire color and size with a different EBTCM pinout except for the following;

SWPS;
Only the 98 SWPS has an analog output and an index signal (marked without JL4 only). Both have the phase A signal, phase B signal, power and ground which are the same wire colors and sizes.

Brake Pressure Differential Switch;
The 98 has one of these. I don't see one on the 04.

So, my conclusion is that any 98-00 with active handling could have the EBTCM changed to the 01-04 unit by installing it and changing the existing connector for the new unit.

I would also suspect the analog part on the old style SWPS is what typically fails meaning I believe the odds are good that you could put the 02-04 EBTCM into a 99-00 car with a failed SWPS and it would still provide the phase A and and phase B signals required by the newer EBTCM.

Now, the 97 and 98 without AH are a little trickier. I'm not sure if the BCM would give the option for the performance driving mode and the lateral accelerometer and yaw rate sensors are missing. This might mean changing the BCM to a model with the AH option or turning on an AH option in the BCM. As for the sensors. The sensors each require the same power and ground that the SWPS already has and they each provide a signal output to the EBTCM. So, the ground and power can be tapped off the SWPS wiring. the SWPS would have the analog output and index output signals that are not needed giving 2 spare wires that could be used for the output signals from these sensor connections.

At this time, I don't need to do this and I don't personally know anyone who would want to do this. So, I'm putting this out there to see what interest there is. Hopefully, others familiar with these systems can comment on any differences they know of.

$$$frumnuttin'

Great stuff....and it all makes sense when you understand how features evolve in the auto industry. The bean counters are hell bent on keeping costs low, so engineering has to make every attempt to carry over current parts, or somehow adapt them if the future design intent can be met.

AllVette

You may also need to consider:

The 2001 and later EBTCM's use dynamic brake proportioning and the earlier units use a mechanical valve.

The Brake Pressure Sensor is located in the BPMV in the later models (rather than in the combination valve), which may or may not produce a different measurement.

The wiring for the SWPS is different on both ends, this will need to be addressed depending on which SWPS is used.

lionelhutz

Doesn't matter as long as it wires up.

Well, that answers the question of the missing brake switch. Also should not matter since the new EBTCM would be used with the BPMV and use the new switch. I didn't describe them separately above but the whole setup EBTCM + BPMV be swapped into the car.

Yes, the plugs are different. If you put a newer SWPS into an earlier car you'll need a harness plug tail. Just like you'll need one for the newer EBTCM.

SteveDoten

When comparing model years, may better to break it down by ebcm location and options,

1. 97, Early 98 (EBCM located on rear xmember) (No AH)
2. Late 98, 99, 00 (Active Handling was an option/JL4)
3. 01-04 (2nd gen Active Handling standard)

dannyman

Thought it may be prudent to re-visit this thread especially this weekend given the fact that the Tadge - GM question is active in the current poll.

If you want a GM response to the replacement of critical parts such as the ECBM and SWPS then the time is now to go to the following link and cast your vote for the C5 camp:

https://www.corvetteforum.com/forums...an-2015-a.html

This is one time where your vote can actually count for something.



Dannyman

Cybermind

Thanks for the link. It looks like "GM parts support for C5's" is winning!

I truly believe GM will begin offering OEM parts for C5's eventually. They can no longer ignore the level of enthusiasm that has developed for our cars and I do believe that the company now has the right people (actual car enthusiasts) in place to make this happen.

Pounder

lionelhutz

It'll be a good attempt, but I expect nothing will come of the question. Most likely, one or more programmable IC's inside the EBTCM are no longer available which makes it impossible to just build new modules. Involving a 3rd party brings up issues of sharing the proprietary technology (the software behind how it operates especially) with this 3rd party. There is a lot of complexity inside that box, and I'd bet that some of the technology is still used by GM on their new cars making GM very hesitant at handing the design to another company to build.

Someone would have to convince the IC manufacturer to make a new batch of components if any of the IC's are out of production. Either that or hope that company would share the design details to another manufacturer willing to do it. Or, the 3rd option is to rely on a Chinese company to reverse engineer the design and hope they get it right (which they often do not).

Bill Curlee

lionelhutz

I wish GM Would hire you to sort this CRAP out and make it GOOD for the 97-2000 C5 owners. You are one of the most dedicated people on the forum for resolving this issue.
YES,, Like you, I agree that resolving the electrical conversion would be pretty much straight forward.

HOWEVER,,,, That being said, Installing a 2001+ BPMV in place of a early BPMV would require a set of all new brake lines... That in its self is a big issue. Its not impossible but,,, probably pretty expensive if not made in a bulk set. You could probably bend a custom set by hand. That would be time consuming and require talent bending lines to make the new BPMV connect to the system.

IMHO,,, I seriously doubt that GM will respond to our VOID of CRITICAL C5 repair parts because,,, They dont have to and its probably NOT profitable.

Just wait until the C6 people start finding NO LONGER SUPPORTED "CRITICAL" C6 PARTS.. LMFAO..

lionelhutz THANK YOU for bringing this topic up again.

Right now The POLL is 210 to 156. 210 for GM Encouragement for C5 Aftermarket Parts & 156 for C6 Z06 Question for Tadge..

We will see what the GM Expert has to say about our issues!

BC

10.5Vette

Wouldn't the 2001 and up brake lines work?

lionelhutz

Bill,

I've made many brake lines over the years. It's actually a fairly easy thing to do for a one-off application. But, I suppose if you wanted to make a kit, one of the companies that makes brake lines for classics could be employed to do it but it'd be pricy.

A while back, Steve posted he'd do the swap to the newer system if a customer was willing to pay him. I wonder if anyone has taken him up on it.

racebum

new swps sensors are on ebay often for 250 shipped

gouging yes but they are OE GM

noticed when i was looking for one for my 02 which thankfully i can get from the dealer