EBTCM Swap possible?
Thread Starter
Burning Brakes
Joined: Feb 2012
Posts: 901
Likes: 2
From: Palm City Fl
EBTCM Swap possible?
My wife's DD is a 99 A4 coupe that she dearly loves. We have owned the car for almost 10 years now. Has some nice mods, headers, high flow catted Xpipe, LS6 manifold, CAI, ect. It runs like a dream, everything is working as it should, with the exception of the 12 disk changer (still working on that). I was wondering if it would be possible to swap the ABS/SWPS/BCM ect... to 01-04 type? Or would it be to costly with all that would have to be changed, if even possible? 
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
My wife's DD is a 99 A4 coupe that she dearly loves. We have owned the car for almost 10 years now. Has some nice mods, headers, high flow catted Xpipe, LS6 manifold, CAI, ect. It runs like a dream, everything is working as it should, with the exception of the 12 disk changer (still working on that). I was wondering if it would be possible to swap the ABS/SWPS/BCM ect... to 01-04 type? Or would it be to costly with all that would have to be changed, if even possible?
BC
Race Director
Joined: Apr 2007
Posts: 11,152
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From: South Western Ontario
Anything is possible. The C5 is the same basic platform for the whole production run.
The wiring between the early active handling (AH) system and the newer system is almost exactly the same. Most of the work is swapping the connector for the newer EBCM. There are just some extra wires for the analog signal from the SWPS that aren't used on the newer system.
A non AH car would require more work to add the 2 missing sensors.
I'm not positive on the steering wheel position sensor (SWPS). The older system has A & B encoder signals plus an analog signal. The newer system has the A & B encoder signals only. I just don't know if those signals are the same. Knowing how GM makes incremental changes I would expect it to work but it may require swapping to the newer sensor.
I'm also not sure on the serial bus side but it seems you can interchange older or newer BCM's and PCM's and dashes so I'd have to believe the newer module would work if your car has AH. You have to do some more work to switch your car to AH if your car doesn't have it so it would control the AH switching correctly.
I'd expect the worst case would be swapping the ABS pump/EBCM and the BCM and maybe the SWPS.
If you paid a shop to do the work I wouldn't be surprised for it to hit $3k in parts and labor so most people won't bother spending that much on a car when they often sell for $10k or less.
The wiring between the early active handling (AH) system and the newer system is almost exactly the same. Most of the work is swapping the connector for the newer EBCM. There are just some extra wires for the analog signal from the SWPS that aren't used on the newer system.
A non AH car would require more work to add the 2 missing sensors.
I'm not positive on the steering wheel position sensor (SWPS). The older system has A & B encoder signals plus an analog signal. The newer system has the A & B encoder signals only. I just don't know if those signals are the same. Knowing how GM makes incremental changes I would expect it to work but it may require swapping to the newer sensor.
I'm also not sure on the serial bus side but it seems you can interchange older or newer BCM's and PCM's and dashes so I'd have to believe the newer module would work if your car has AH. You have to do some more work to switch your car to AH if your car doesn't have it so it would control the AH switching correctly.
I'd expect the worst case would be swapping the ABS pump/EBCM and the BCM and maybe the SWPS.
If you paid a shop to do the work I wouldn't be surprised for it to hit $3k in parts and labor so most people won't bother spending that much on a car when they often sell for $10k or less.
Last edited by lionelhutz; Jul 11, 2014 at 05:51 PM.
Thread Starter
Burning Brakes
Joined: Feb 2012
Posts: 901
Likes: 2
From: Palm City Fl
I'm not looking to replace any of it while it is working just fine. I am just thinking about if it does go out. Thinking if I could pick up a car that was a total from rear end or side damage , I could pull the ABS pump, EBTCM, BCM, SWPS, break lines and wiring harnesses needed for the swap and part out the rest of the car. 
Be quite the undertaking, but think it would be fun and interesting too. As long as I don't end up with to junk cars
