Traction control programming, In tranny or car?

[darknezz7]

Short story is I had a wrecked 94 530 with a good engine and tranny that DID NOT have traction control. I got a Nice 94 530 with a seized engine that DID have traction control. I dropped the engine and tranny from the non TC 530 into the one with TC. It said trans program and was slipping or in limp mode.

Pulled it back out and put the tranny from the car with traction control on the good engine. I changed the fluid and filter this time when I did this. Put it back in has been running great 15k miles!

What I need to know:

Is there programming in the transmission its self for the traction control to go with the car?
If so how can I use a NON TC tranny in a TC Car?

If not what caused my other tranny to slip or be in limp mode, its was probably very low on fluid, would that cause trans program?
After the crash it was still driving, even drove it up on the tow truck the next day.

If someone could explain traction control to me a little bit that would be great! All I notice when I use the TC switch is is SLOWER, my old car Id have it in "M" mode and ti would be faster, TC SUCKS! If theres a way to reprogram or swap modules to make the car have "manual" mode instead of TC that would be great.

What I would like to do one day is have my extra tranny rebuilt and chipped and drop it in when I get a new 4 liter m60. Though I might just be selling it and get a real 540 and rebuild the engine for more performance and reliability.

Thanks to any replies, last time I asked about this no one posted but maybe I worded it better this time?

[billbarr]

Originally Posted by darknezz7

Short story is I had a wrecked 94 530 with a good engine and tranny that DID NOT have traction control. I got a Nice 94 530 with a seized engine that DID have traction control. I dropped the engine and tranny from the non TC 530 into the one with TC. It said trans program and was slipping or in limp mode.

Pulled it back out and put the tranny from the car with traction control on the good engine. I changed the fluid and filter this time when I did this. Put it back in has been running great 15k miles!

What I need to know:

Is there programming in the transmission its self for the traction control to go with the car?
If so how can I use a NON TC tranny in a TC Car?

If not what caused my other tranny to slip or be in limp mode, its was probably very low on fluid, would that cause trans program?
After the crash it was still driving, even drove it up on the tow truck the next day.

If someone could explain traction control to me a little bit that would be great! All I notice when I use the TC switch is is SLOWER, my old car Id have it in "M" mode and ti would be faster, TC SUCKS! If theres a way to reprogram or swap modules to make the car have "manual" mode instead of TC that would be great.

What I would like to do one day is have my extra tranny rebuilt and chipped and drop it in when I get a new 4 liter m60. Though I might just be selling it and get a real 540 and rebuild the engine for more performance and reliability.

Thanks to any replies, last time I asked about this no one posted but maybe I worded it better this time?

You can go to www.car-part.com and get an idea what trans is interchangeable by the questions they ask.I think you may have to reset the trans controller after a swap or swap the controller with it.I believe traction control is in conjunction with the antilock brake system and it senses the slipping thru the wheel speed sensors.

[thejlevie]

Is there programming in the transmission its self for the traction control to go with the car?

No

If not what caused my other tranny to slip or be in limp mode, its was probably very low on fluid, would that cause trans program? After the crash it was still driving, even drove it up on the tow truck the next day.

Low fluid could do it, or there could have been damage from the accident.

[darknezz7]

I should add that while I had the non TC tranny in the car I did try swapping the gearbox controller computer and I'm using the engine computer from the wrecked car, the one that went with that engine.

I'm kinda thinking it was just low fluid, I kinda always have.
I don't think its damaged from the accident because it still drove the next day onto the flatbed and the damage was just in the front end and the frame. I can't remember if it was saying trans program and slipping then or not, it was not a good time...

Is there electronics in the tranny at all to remember if the car was in an accident and be stuck in limp mode needing some kind of reset?

Otherwise I think it was just the fluid and its probably fine.
Its allways good to have an extra AUTO tranny
Thanks!

[thejlevie]

There are no electronics in the transmission. A quick check of realoem.com only shows one transmission part number, which implies that the differences between those two cars are external to the transmission.

[darknezz7]

I got that the TC isn't in the transmission, there are electronics in the transmission because there's a larger plug the goes into it.

So its not posible they have a fail safe to put the transmission in limp mode after an accident?

If that's not possible then it must have been the fluid.

Thanks for finally helping me figure out if I got a good spare tranny!

[thejlevie]

The transmission does have electrical parts in it and its operation is controlled by the transmission computer, hence the electrical plug. I've never heard of anything that would force fail safe mode after an accident, but there is the possibility of damage to the transmission just from the g forces in an accident. If the transmission was seriously low on fluid, that would be a reasonable explanation for it not working properly.

[bmwdirtracer]

All the above is true. On the other hand, a "trans program" code needs to be read, and erased, too. Reading the stored code will likely take you to the issue. But a trans which has incorrect fluid level will certainly cause slipping and codes, and the accident may well have caused leaks.

Other issues, including engine and abs sensor issues, can also cause transmission codes and "limp" operation..

[moroza]

Can't help you with the trans itself.

The traction control (ASC or ASC+T) electronics are integrated into the ABS module. On cars that have it, this module interfaces with the DME (engine computer) and EGS/AGS (auto trans computer). ASC would almost certainly not throw transmission codes - it has its own light for its own faults.

You threw the 530i's trans into the 540i's body, still using the 540i's trans computer? If so, that sounds like your problem - the two transmissions are physically different units and require their respective modules.

There is wiring in place to effect limp mode following an accident, but I don't see why they would've done that. On the other hand, they've done other things that make even less sense, so there may indeed be a post-accident limp code stored.

ASC+T is not easy to delete, unfortunately. You have to do a fair bit of wire splicing and source a new ABS hydro unit and control module. I did it on my 530iT project and it was a long and tedious mess (and I don't even know if it works yet, TBH). In a nutshell, ASC adds a second throttle plate in front of the main one; when it thinks you're giving the engine too much power, it throttles it back. ASC+T also adds the capability for the car to apply the rear brakes when it feels like it.

[darknezz7]

Thanks for the explanation of TC, SOUNDS LIKE I HATE IT MORE.
Both cars were auto 530i's with the same hp5zf18 trannies.

There's definitely no "second throttle plate"

The switch by the shifter in my old car had the manual mode, this one has the *, is traction control allways on or just when I activate the *