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      02-06-2017, 07:42 PM   #89
RyanDavies
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You never want RAB. It is inconsistent, which is the biggest problem with it.
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      02-07-2017, 06:58 PM   #90
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Found a 1M trace file to pull values and compare to.. I used the TRC file provided by someone earlier in this thread for a 135i without active steering. I'm not sure if his car was a manual or automatic.

Main variables from this thread:
Code:
DIFF_LOCK // e-diff
135i: wert_02
1M:   wert_00

FBS // Brake Fading Compensation
135i: wert_01
1M:   wert_01

FLR // Engine Power Reduction to Prevent Brake Disc Overheating
135i: wert_01
1M:   wert_00

BB_RAB // Ready Alert Brake
135i: wert_01
1M:   wert_01
Other interesting parameters with differences in DSC module:
Code:
ASC_AMR_STB // Drive torque control
135i: wert_03
1M:   wert_00

BBV_KORR_VA // Brake Pad Wear Compensation, Front Axle
135i: wert_02
1M:   wert_00

BBV_KORR_HA // Brake Pad Wear Compensation, Rear Axle
135i: wert_02
1M:   wert_01 (C08)

DELTA_PSI_BETA_LIMIT // Delta-Psi-Beta Limit Correction
135i: wert_01
1M:   wert_00

DELTA_PSI_BETA_LIMITKORR2
135i: <value does not exist>
1M:   wert_01

DRUCKMODELL_VA // Pressure Model Front Axle
135i: wert_06
1M:   wert_00

DRUCKMODELL_HA // Pressure Model Rear Axle
135i: wert_05
1M:   wert_00

GMK_ECBA_HA // Yaw Moment Compensation Effective Friction Radius, Rear Axle
135i: wert_02
1M:   wert_02 (base value is wert_02, all C0X values are wert_00, not sure what true value is)

LENKWINKELKENNLINIE // Steering Angle Characteristic Curve
135i: wert_03
1M:   wert_00

UEBERSTEUERN_MUE_0 // Understeer Friction Coefficient 0
135i: wert_04
1M:   wert_00 (base value is wert_01, C04 value is wert_04, others are wert_00, not sure what the true value is)

UEBERSTEUERN_MUE_1_2 // Understeer Friction Coefficient 1 2 [DATA<128 ? COEFFICIENT = 2.5 + (DATA/64) : COEFFICIENT = 2.5 + ((DATA/64-256)/64)]
135i: wert_05
1M:   wert_00 (base value is wert_01, C04 value is wert_04, others are wert_00, not sure what the true value is)

UNTERSTEUERSCHWELLE // Understeer Threshold
135i: wert_01
1M:   wert_00 (C03 is wert_02, C04 is wert_04, others are wert_00)
If you're interested in looking at the FSW_PSW.TRC file directly, you can find it at bmw coding dot com page (search for "2011 E82 1M" in "FSW PSW Trace and VO dumps" forum).
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      04-02-2017, 04:54 PM   #91
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Would disconnecting the yaw sensor yield the results you guys are after? It will light up the xmas tree but there is no DSC intervention because it has no yaw data input to determine under/oversteer.

Im not sure if it plays a role in traction control or the ediff - could those be purely wheel speed sensor determined?
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      04-03-2017, 11:24 PM   #92
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Quote:
Originally Posted by juld0zer View Post
Would disconnecting the yaw sensor yield the results you guys are after? It will light up the xmas tree but there is no DSC intervention because it has no yaw data input to determine under/oversteer.

Im not sure if it plays a role in traction control or the ediff - could those be purely wheel speed sensor determined?
Sure, but that would also totally turn off DSC. I think I speak for most people here when I saw we're not trying to totally kill off all the DSC systems, we just want to be able to truely turn them off when we want to (and always have the ediff disabled).

Also it wouldn't do anything to disable FBS, FLR or BB_RAB since those don't need any yaw data.
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      04-09-2017, 04:54 PM   #93
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I finally got my coding laptop set up so i'm having a play.

Do X drive models still have the Ate/Continental/Teves MK60E5 DSC module? I've seen no literature that suggests the MK60E5 is capable of Xdrive control. We don't get the N55 version here and even N52 X1s are very rare. Majority of X1s here have a Bosch DSC8 module and if that is shared across all E84 that might be why the item names are different and the wert_00 vs nicht_activ variances.

So far i have disabled:
- RAB
- FLR
- FBS

I'm really just looking to improve brake pedal response consistency rather than kill the ediff as I dont have an LSD. Brake inconsistency is the biggest nuisance of this car
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      06-12-2017, 07:50 AM   #94
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Has anyone changed the understeer friction and steering angle compensation codes on the 135?

I would guess these are tied into the e-diff or power reduction.
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      06-15-2017, 11:26 AM   #95
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Quote:
Originally Posted by drwillb View Post
Has anyone changed the understeer friction and steering angle compensation codes on the 135?

I would guess these are tied into the e-diff or power reduction.
I changed it on my 335i. The understeer and overseer friction just gives you more ability to slide around corners but traction still intervene on my car when I get too far out of line. With dsc full off. The extra sliding doesn't feel good on to me though and can slow you down. You can make it slide less too. Car sticks better but with a tune power can't be fully applied to the ground due to traction intervention. Very frustrating.
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      06-15-2017, 11:30 AM   #96
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Quote:
Originally Posted by YarkoDrives View Post
have you had this done yet? Is this on an N55? What shop?

I like the idea, but after some testingI doubt it would work without a piggyback ecu.

the DSC/ABS connection to the DME is not a simple connection between the two modules. they are both on the PT-Can bus (PT= Powertrain) with other modules like the combi-dash, HVAC controller, starter controller, etc.

Today I tested some:

disconnecting the ABS/DSC from the PT-Can bus:
a. no speedometer, as there is no wheel speed data from the DSC to the combi
b. lots of warning lights
1. air bag - air bag is dependant on speed/accelrometer data from DSC
2. service - yeah I know something is out of sorts
3. DSC inactive - yeah that's a desired state
4. ABS - Red light - not true, the ABS works fine, but the combi cannot see the module.

c. wipers run constantly- just in case you didn't notice all the lights this will encourage you to go to a dealership or pull the wiper fuse.

d. rev limit around 4500 to 4800 - maybe this is the combi assuming the car is in 6th gear, as there's no speed data to calculate the gear with, and enforcing the top speed limit regardless of the actual gear. Can the top speed limit be coded off?

e. there was however no problem making boost, and the car behaved like an open diff. abs was fine.


Then for an additional test I tried the other side, which is disconnecting the PT-can from the engine. This was no good:
a: no tach or oil temp on the combi
b. no boost -- ? limp or lack of data from? - the boost controlled directly by DME or by another module.
c. starter runs for full 3 seconds, even after engine is running.
d. fan runs on full high - without engine data, assumes it is hot hot
e. AC compressor runs on minimum output, without data assumes it is high rpm.
f. still rev limit around 4500, not sure eaxctly as I have no tach, but I cannot get up to highway speed of 55mph in second gear.

I don't think most of these are issues that can be coded away, as they are mostly caused by lack of data between modules on the PT-bus.

It would be cool if they could be, again let me know the shop.

There may be a sweet spot to splitting the PT-can in to two, where the DSC and the engine are isolated, and the engine has access to the modules it needs, while the DSC is alone.

obviously a piggyback tune could avoid some of the issues.

I'm curious what that shop is doing, and if it is on N55's. Let me know I'd like to believe.
Did you simply pull the Dsc connector off the Dsc module or was there more to it?
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      06-16-2017, 04:51 PM   #97
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No, for these test we cut one of the the can bus wire pairs at the ABS and DME.

The connector at both of these has lots of other wires too.

-----------------

FWIW we ended up just disconnecting the DSC accelerometer under the drivers seat.
- It's a simple connector plug to disconnect
- Reattaching it clears the warning lights without any error set.
- Disconnecting the sensor is legal mod to defeat traction control for SCCA solo Street class.
-- SCCA issued a technical bulletin last year the coding the traction control programs to different factory settings with a factory tool/ software wasn't legal in STREET class. (probably is in Street Touring)
the accelerometer sensor disconnected
-gives the yellow brake warning light.
-defeat the anti-trailbrake anti-overstear program
-defeats all the oversteer and understeer TCS programs
-defeats the Hill hold launch function in Manual Trans cars

downshift rev-match, e-diff, abs, wheel-speed based brake biasing, brake pre-tension on quick throttle lift, and brake fade prediction are still active.
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      06-16-2017, 05:07 PM   #98
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Quote:
Originally Posted by juld0zer View Post
Would disconnecting the yaw sensor yield the results you guys are after? It will light up the xmas tree but there is no DSC intervention because it has no yaw data input to determine under/oversteer.

Im not sure if it plays a role in traction control or the ediff - could those be purely wheel speed sensor determined?

The ediff seems to work on front wheel speed vs real wheel speed.

running square 245/40/17 in autocross the program would intervene. Since I changed the rear to taller 145/45/17 the ediff program has no come in.

I assume that the front wheel speed sensors determine the vehicle speed and anything over a small percentage of that same speed would be interpeted as slip and trigger the program on the rear.

with no slip, both ends going the same speed, the taller rear tire is going at 96% of hub wheel speed of the front. So If I get 5% slip the car thinks it is still at zero.

not sure what the threshold percentage is for slip to trigger the eDiff, but I've not gotten there since the staggered height on rear.

-- been a while since i looked thru the coding options, but there might be a percentage of slip threshold on the ediff program that could be changed.

I'm not endorsing running a tall rear tire, I only do it for autocross, as it help induces oversteer on the stock springs..
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      06-16-2017, 05:46 PM   #99
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Quote:
Originally Posted by YarkoDrives View Post
No, for these test we cut one of the the can bus wire pairs at the ABS and DME.

The connector at both of these has lots of other wires too.

-----------------

FWIW we ended up just disconnecting the DSC accelerometer under the drivers seat.
- It's a simple connector plug to disconnect
- Reattaching it clears the warning lights without any error set.
- Disconnecting the sensor is legal mod to defeat traction control for SCCA solo Street class.
-- SCCA issued a technical bulletin last year the coding the traction control programs to different factory settings with a factory tool/ software wasn't legal in STREET class. (probably is in Street Touring)
the accelerometer sensor disconnected
-gives the yellow brake warning light.
-defeat the anti-trailbrake anti-overstear program
-defeats all the oversteer and understeer TCS programs
-defeats the Hill hold launch function in Manual Trans cars

downshift rev-match, e-diff, abs, wheel-speed based brake biasing, brake pre-tension on quick throttle lift, and brake fade prediction are still active.
I've disconnected the accelerometer sensor and didnt notice too much difference. I still feel braking on the front or rear wheels or torque reduction when cornering. I think the ediff is also relying on data from the steering angle sensor. The car always puts a limit on my cornering power to keep me from spinning no matter how far I press the accelerator. Running high boost allows me to launch the car with wheels spinning but the DME will not allow wheelspin once I'm already rolling like it use too. Shifting into 2nd and 3rd gear wants to spin but power is reduced just enough to stop the spin and lurch forward.

I'm wondering if this is unique to my car sense I'm experiencing torque and boost reduction, braking like ASC would do. Disconnecting the DSC module doesnt prevent this so i feel like the steering angle sensor is reporting info to the DME. I dont know how else the car would know im turning as oppossed to going straight ahead. I get alot of wheelspin with straight forward launches. As soon as i turn the steering, the torque is reduced at the engine not with braking even in 1st gear. It's really interesting to throw the car in 1st gear while turning a corner and get no wheel spin. I get just enough forward motion to keep tires planted. Once the wheel straightens out, the car launches. Very nice for safe driving but not for fun driving. Have you noticed this with your experiences?

I may try disconnecting all 4 speed sensors or the steering angle. Disconnecting 1 rear wheel speed sensor didint do the trick. I'm not even trying to slide the car. I just want to be able to accelerate and control the power in the corner without power reduction.
Is ediff reducing power on you like this?

Last edited by brakthru; 06-16-2017 at 06:01 PM..
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      07-08-2017, 10:28 PM   #100
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Is anyone running an auto transmission and a jb4? I noticed if I disable Watergate adaption/learning in jb4 settings it limits traction intervention and allow jb4 to have more boost control. I can power through corners better and put more power down in the straights. Apparently, the car controls the wastegate even with a jb4 installed which will limit boost. My car is loading up the suspension more as the car leans or rolls more in corners on the front tires and rear tires. I haven't seen outer treadwear in a while since abs/traction keeps the car on all 4s pretty good with very little pitch.

I'm really not sure why all of this is happening but it feels nice. There is still some intervention with steering angle in extreme cases which is good. Your not really going anywhere safely with too much loss of traction.


Can someone try this out and post results.
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      07-11-2017, 10:03 AM   #101
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Quote:
Originally Posted by brakthru View Post
Shifting into 2nd and 3rd gear wants to spin but power is reduced just enough to stop the spin and lurch forward.

As soon as i turn the steering, the torque is reduced at the engine not with braking even in 1st gear. It's really interesting to throw the car in 1st gear while turning a corner and get no wheel spin. I get just enough forward motion to keep tires planted.
Once your moving the vehicle uses a downshift rev match program:
front wheel speed sensors determine the vehicle speed, and throttle is cut to match RPMs.

I don't believe there is a gate sensor on the MT selector. The program assumes a downshift of 1 gear. based on braking?

You could try skipping from 4th to 2nd and see if you can get wheel slip.
-- The Shift program may just be a part of the intervention.
-- I got rid of my 135, and am running a 128 now.


Another option is to run slightly taller rears. then the program allows the rear wheels to be running a little faster (the same RPM on a larger circumference). With this configuration on my 128 I can lose the back end if I don't rev match. It should have a dramatic effect on the 135.

Also an advantage of the tall tire is it adds margin to the eDiff slip limit, as the rear wheels are normally spinning at a slower RPM than the fronts, the program rarely can see rear slip.

I'm running 245/40/17 Front and 245/45/17 rear.
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      07-11-2017, 10:30 AM   #102
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Quote:
Originally Posted by YarkoDrives View Post
Once your moving the vehicle uses a downshift rev match program:
front wheel speed sensors determine the vehicle speed, and throttle is cut to match RPMs.

I don't believe there is a gate sensor on the MT selector. The program assumes a downshift of 1 gear. based on braking?

You could try skipping from 4th to 2nd and see if you can get wheel slip.
-- The Shift program may just be a part of the intervention.
-- I got rid of my 135, and am running a 128 now.


Another option is to run slightly taller rears. then the program allows the rear wheels to be running a little faster (the same RPM on a larger circumference). With this configuration on my 128 I can lose the back end if I don't rev match. It should have a dramatic effect on the 135.

Also an advantage of the tall tire is it adds margin to the E-Diff slip limit, as the rear wheels are normally spinning at a slower RPM than the fronts, the program rarely can see rear slip.

I'm running 245/40/17 Front and 245/45/17 rear.
You do quiet a bit of speculating here that I don't think is accurate.

E-diff's goal is to maintain a <5% wheel speed differential (Per Bosch documentation). If you run different aspect ratio ties in the rear all you will do is allow that wheel to spin at a maximum of 9.99% difference between the others wheels (granted the other 3 are all spinning at the same exact speed). I got that numbers by assuming your taller aspect tires are seen by the wheel speed sensors as spinning -4.99% slower than the front tires. This won't cause any intervention as is, but as soon as it starts to spin freely upon cornering the e-diff won't brake the wheel until it starts spinning 5% faster than the other wheels (-4.99 to +5% = 9.99% wheel speed difference).

Allowing the inside wheel to spin freely is not a good thing so not sure why you see this as a benefit. You won't be "losing the back end" in corners, you'll simply be spinning the inside tire more. Straight line acceleration is a mute point... E-diff will allow burnouts so long as both rears tires spin freely within 5% of each-other (Burnouts are hard to do since axel shafts are different lengths and more power always gets delivered to one wheel). Raising the ceiling to 10% differential, as seen above, will just allow you to smoke your tires for a bit longer. Once again, not exactly a benefit to spin tires in a timed event

E-diff is not a traction control system, so I don't see why the regulation you quoted would have any bearing on eliminating the e-diff with coding. I can tell you right now, disabling the e-diff without a mechanical LSD is not fun. You will be much slower as you will constantly be spinning the inside wheel and throwing up clouds of smoke lol.

The DSC system does indeed using steering angle as well as accelerator data to determine slip angle. Simply holding the traction control button down for 5seconds turns DSC functionality completely off leaving only e-diff on. Again, why would this be illegal? The 5 second hold turns off ALL assistance like corner braking control (on carslike the 1M), ASC, and DSC. I have no clue if disabling the accelerator will disable traction control entirely... I would think that you'll still get dynamic traction control intervention (ASC) since traction control doe snot make use of the yaw sensor... Then again, usually all systems go down when 1 sensor fails (the trifecta lights you describe seeing when you disconnected the yaw sensor)...

The other functions you quoted, like Rain disc drying, brake disc overheating, brake pre-tensioning, and brake fade compensation are all separate functions that are not effected by coding the e-diff off or by turning DSC off...

If you want to be able to run a bit of slip angle, then simply single click the traction control button... it won't allow you to swing the tail out as much as "track mode" on an M-series car, but you'll still be able to swing it out a bit while maintaining SOME level of traction control. personally, I always keep DSC 100% off...

Source:
Lots of documentation out there on how theses systems work:
DSC document: https://bmw.spool
street.com/documents/e90-dynamic-driving-system-dsc-module.22/

Quick video:

Last edited by bNks334; 07-11-2017 at 11:05 AM..
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      07-11-2017, 11:01 AM   #103
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Quote:
Originally Posted by brakthru View Post
Is anyone running an auto transmission and a jb4? I noticed if I disable Watergate adaption/learning in jb4 settings it limits traction intervention and allow jb4 to have more boost control. I can power through corners better and put more power down in the straights. Apparently, the car controls the wastegate even with a jb4 installed which will limit boost. My car is loading up the suspension more as the car leans or rolls more in corners on the front tires and rear tires. I haven't seen outer treadwear in a while since abs/traction keeps the car on all 4s pretty good with very little pitch.

I'm really not sure why all of this is happening but it feels nice. There is still some intervention with steering angle in extreme cases which is good. Your not really going anywhere safely with too much loss of traction.


Can someone try this out and post results.
All you are describing here is proper tuning that dials boost (torque) in more slowly... More power isn't a good thing if you can't put it to the ground.

Running stock tune in autocross can be faster than a tuned 135i since the courses are so short and performed in low gears... the car already has enough boost/torque stock to spin 1st through 2nd on command.
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      07-14-2017, 01:13 AM   #104
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Quote:
Originally Posted by bNks334 View Post
You do quiet a bit of speculating here that I don't think is accurate.

E-diff's goal is to maintain a <5% wheel speed differential (Per Bosch documentation). If you run different aspect ratio ties in the rear all you will do is allow that wheel to spin at a maximum of 9.99% difference between the others wheels (granted the other 3 are all spinning at the same exact speed). I got that numbers by assuming your taller aspect tires are seen by the wheel speed sensors as spinning -4.99% slower than the front tires. This won't cause any intervention as is, but as soon as it starts to spin freely upon cornering the e-diff won't brake the wheel until it starts spinning 5% faster than the other wheels (-4.99 to +5% = 9.99% wheel speed difference).
exactly what I experience, e-diff program now has a margin of ~10% vs. ~5%. I do not experience the ediff program intervening anymore because I keep wheel slip well under 10%. In autocross on the lots we use, with my alignment, and my dumb right foot I was often getting into the ediff program. Both of my coaches, one with several Solo national championships were also getting into the ediff on some corner exits in the 135is.

Quote:
Originally Posted by bNks334 View Post
Allowing the inside wheel to spin freely is not a good thing so not sure why you see this as a benefit. You won't be "losing the back end" in corners, you'll simply be spinning the inside tire more. Straight line acceleration is a mute point... E-diff will allow burnouts so long as both rears tires spin freely within 5% of each-other (Burnouts are hard to do since axel shafts are different lengths and more power always gets delivered to one wheel). Raising the ceiling to 10% differential, as seen above, will just allow you to smoke your tires for a bit longer. Once again, not exactly a benefit to spin tires in a timed event
I'm running SCCA Solo. So It's not straight line tire-smoking slip.

Here's where ediff is a problem:
on the 128 at speeds of 25-40mph in tight dual hairpin/chicane type elements the inside wheel may slip due to throttle or a bump, the ediff program takes a moment to come in, by the time it comes in the car is already turning the opposite direction and is loaded on the opposite side, so the ediff is now braking the unloaded wheel inside wheel. the power goes to that wheel, and the ediff program come in again. this braking creates an icey - unable to accelerate state.
Over the prior two season, running same size tires I encountered the ediff intervention slowing the car almost every event, and experienced the long (1 second+) intervention in a tight chicane 3 or 4 times.

So far this season in the 128, I've done 9 events with the taller rears I have only gotten into the ediff program once.. 1st run and a corner exit was on a slippery patch, and I lit up the tire. the ediff slowed the axel the program hung around after the car was hooked up. I took it easier on the following runs.


on the 135is the power and boost lag made it a poor choice for autocross, everyone that drove my car got into the ediff , we found that when the ediff came in it was best to stay on the throttle and let the program do its thing.

Quote:
Originally Posted by bNks334 View Post
E-diff is not a traction control system, so I don't see why the regulation you quoted would have any bearing on eliminating the e-diff with coding. I can tell you right now, disabling the e-diff without a mechanical LSD is not fun. You will be much slower as you will constantly be spinning the inside wheel and throwing up clouds of smoke lol.
The ABS unit has ABS, brake biasing, and a lot of programs, including the e-diff program, for SCCA they are all traction control programs or ABS. I see it as traction control, inputs are wheel speed sensors, corrective action is braking.

The e90 and e82have Continental Teves MK6...v5.. ABS/DSC, though It probably does work about the same as the Bosch systems.

SCCA solo street rules are pretty strict on electronics & coding. It only allows unplugging or sending modified signals to a sensor.


Quote:
Originally Posted by bNks334 View Post
If you want to be able to run a bit of slip angle, then simply single click the traction control button... it won't allow you to swing the tail out as much as "track mode" on an M-series car, but you'll still be able to swing it out a bit while maintaining SOME level of traction control. personally, I always keep DSC 100% off...
the 2013 128i and 2013 135is maintain some of the traction control modes after you hold the button down for 5 seconds. CBC is one of that stays on. in "DSC off mode" the oversteer correction amount is too severe for a car that is already on edge at an autocross. With DSC held down and "off" I had several spins that were caused by Traction control. They occurred in the direction opposite the way I was loading the car in a steady state drift.


Quote:
Originally Posted by bNks334 View Post
You do quiet a bit of speculating here that I don't think is accurate.
yes, a lot of development on the car is started with speculation and trial and error.

I'm speaking from my experience with the car.

I appreciate the skepticism.

I'm getting a CAN data logger so I can confirm some things with data.
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      07-14-2017, 08:53 AM   #105
bNks334
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Quote:
Originally Posted by YarkoDrives View Post
I'm speaking from my experience with the car.

I appreciate the skepticism.

I'm getting a CAN data logger so I can confirm some things with data.
I know exactly what you mean with E-diff intervention, it slows you down. It is braking wheels after-all... My personal experience has been that allowing the wheels to spin freely from one another doesn't make you any faster. The car will just FEEL different at the limit (smoother acceleration when laying down power since e-diff can get get choppy when applying brakes) but an open diff will be slower overall. I am talking about running with traction control fully disabled (5 sec click).

I am confused though. If you aren't disabling DSC when you drive, how are you determining it's the e-diff function that is causing what you describe? What you seem to be describing is not e-diff intervention. You seem to be describing what happens when DSC/TC cuts in... DSC/TC will cut power to keep slip angles and wheel spin in check and causes a bit of a delay before you can get back on the gas... that's not the e-diff doing that. I posted the video that explains this.

I don't see how you could possibly want to leave DSC on because you can't control your car (spin outs) but then want to disable the e-diff? DSC/TC will intervene to prevent tire spin whereas the E-diff actually doesn't prevent wheel spin at all. As previously mentioned, the E-diff just keeps both wheels spinning at the same speed to maximize power to the ground. You can drift around the autocross course all day with the e-diff...

Yes, you are correct in that both cars use the Teves Mk60 unit (and the 3 -series). Review the E90 DSC module PDF I posted that explains everything the functions do any why... Also, I have owned both cars too, and have coded both cars extensively. CBC isn't a working function on 128i/135i's. CBC is a more robust function that only the 1M got. 128/135i has the ASC function "dynamic traction control" (single click of the traction control button). Holding down the traction control button for 5 seconds does indeed disable ALL traction control functionality on both cars. The exceptions to that are the e-diff and the aforementioned functions like brake pre-tensioning, brake disc overheating, etc...

Also, I have posted both trace files of the mk60 dsc module side by side in this thread back on page 2 (https://docs.google.com/spreadsheets...it?usp=sharing). There is actually very little differences in the coding between a 128 and a 135i. The few parameters that do differ are some slip angle characteristic and brake characteristics settings. These are different values to address the different weight bias and brake torque of the 135i. That's all that differs. Both systems behave exactly the same because they simply are exactly the same.

Another consideration is that these cars beg for a throttle re-mapping. The stock throttle map goes from 20% to 80% load within the first 10% pedal movement (a bit of a hyperbole but you get the idea). The gas pedal works like an on/off switch from the factory. Makes the car feel peppy but difficult to modulate power at the limit... I mention this because it sounds like modulating the throttle is your main issue. Again, another thing you can't modify in street trim.

Last edited by bNks334; 07-14-2017 at 10:42 AM..
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      08-30-2017, 06:53 AM   #106
juld0zer
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Quote:
Originally Posted by bNks334 View Post
Can anyone shed any light on the following (compared my TRC to an 09 335i):

C0F_LENKWINKELKENNLINIE (STEERING ANGLE CHARACTERISTIC CURVE)
13 base 128i = wert_03
09 335i = wert_00 & wert_01

C0F_SCHUBABSCHALTUNG (DECELERATION FUEL CUT-OFF [WERT_00: DISABLED, WERT_01: ENABLED]
13 base 128i = wert_00
09 335i = wert_01

-Is it possible to simply activate this? It cuts fuel to save gas when coasting downhill...

C0F_DBC_MIN_AUSLOESEDRUCK (DYNAMIC BRAKE CONTROL (DBC) MINIMIUM RELEASE PRESSURE)
13 base 128i = wert_00
09 335i = wert_00
Data: E4

-There is no other setting for this but the data value is populated so is it active? Seems like if "data" is "0" then whatever settings you're looking at is not active. Since there is data in wert_00 in this case it probably IS doing something?

C0F_CBC (CORNERING BRAKE CONTROL (CBC))
13 base 128i = wert_00
09 335i = wert_00
Data: 0

-Again, there is no other setting for this and the data value is "0" so does that mean no CBC for either model?

If anyone has an m-sport TRC I can look at please paste it! At this point all I can conclude is that 128i/335i models don't have half the crap to code that the x1 has in the MK60 module.
I enabled C0F_SCHUBABSCHALTUNG on my N55 DCT to try something. Hated it, coded it back to standard as soon as i could. On the DCT it disengages the clutch but the current gear is held. Revs drop to about 1200rpm but when you come to accelerate again, there is a delay as the clutch has to be re-engaged. Before i modified it, it was set to wert_00. Perhaps the manual cars have it set to On? It would make more sense on a manual
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      09-13-2017, 07:17 AM   #107
juld0zer
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Quote:
Originally Posted by YarkoDrives View Post
have you had this done yet? Is this on an N55? What shop?

I like the idea, but after some testingI doubt it would work without a piggyback ecu.

the DSC/ABS connection to the DME is not a simple connection between the two modules. they are both on the PT-Can bus (PT= Powertrain) with other modules like the combi-dash, HVAC controller, starter controller, etc.

Today I tested some:

disconnecting the ABS/DSC from the PT-Can bus:
a. no speedometer, as there is no wheel speed data from the DSC to the combi
b. lots of warning lights
1. air bag - air bag is dependant on speed/accelrometer data from DSC
2. service - yeah I know something is out of sorts
3. DSC inactive - yeah that's a desired state
4. ABS - Red light - not true, the ABS works fine, but the combi cannot see the module.

c. wipers run constantly- just in case you didn't notice all the lights this will encourage you to go to a dealership or pull the wiper fuse.

d. rev limit around 4500 to 4800 - maybe this is the combi assuming the car is in 6th gear, as there's no speed data to calculate the gear with, and enforcing the top speed limit regardless of the actual gear. Can the top speed limit be coded off?

e. there was however no problem making boost, and the car behaved like an open diff. abs was fine.


Then for an additional test I tried the other side, which is disconnecting the PT-can from the engine. This was no good:
a: no tach or oil temp on the combi
b. no boost -- ? limp or lack of data from? - the boost controlled directly by DME or by another module.
c. starter runs for full 3 seconds, even after engine is running.
d. fan runs on full high - without engine data, assumes it is hot hot
e. AC compressor runs on minimum output, without data assumes it is high rpm.
f. still rev limit around 4500, not sure eaxctly as I have no tach, but I cannot get up to highway speed of 55mph in second gear.

I don't think most of these are issues that can be coded away, as they are mostly caused by lack of data between modules on the PT-bus.

It would be cool if they could be, again let me know the shop.

There may be a sweet spot to splitting the PT-can in to two, where the DSC and the engine are isolated, and the engine has access to the modules it needs, while the DSC is alone.

obviously a piggyback tune could avoid some of the issues.

I'm curious what that shop is doing, and if it is on N55's. Let me know I'd like to believe.
That is totally the wrong way to do it.
PT CAN is a twisted pair for redundancy reasons. If one wire gets cut for whatever reason (f
chafed, burnt, corrosion, loose etc) then the second wire will carry the signal at a lower rate to allow you to limp home. This is what you experienced.

When scoped, PT CAN signals are a mirror image of each other.

On the E9x and E8x, a lot of signals go through the Junction Box Electronics. This is the central hub or gateway for control units to talk to each other and greatly simplifies the interconnection of several control units - such as the DSC, DME and EGS. Eg. EGS requires wheel speed and engine speed to determine which gear to be in.

Therefore when you cut out one control unit, functions of another will be affected, like you observed.

You are best to disconnect the sensor which feeds the data required for the system you are trying to disable.
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      02-13-2018, 04:47 PM   #108
BoostedBarrett
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I just got my M Factory LSD on my 135.
I would like to have all this crap turned off for track days. Is it possible to turn it all off when dsc button is turned on, or does it all have to stay off all the time? Also, is there someone on the forums that helps you with this sort of thing for money? IF so, please message me.
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      02-14-2018, 06:13 AM   #109
bionicbelly
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Quote:
Originally Posted by BoostedBarrett View Post
I just got my M Factory LSD on my 135.
I would like to have all this crap turned off for track days. Is it possible to turn it all off when dsc button is turned on, or does it all have to stay off all the time? Also, is there someone on the forums that helps you with this sort of thing for money? IF so, please message me.

I just got my cable from bimmergeeks. The cable is about $45 and he will turn off all the stuff you want for about $60. It is a fantastic deal in my opinion. I have so many other things to do, and don't want to spend the time learning and experimenting with this.

Not sure if you can code stuff like this to be turned on and off with the dsc button or not, but I do know that anytime I have messaged bimmergeeks, I have had a response in minutes. Pretty sure he would know.

https://www.bimmergeeks.net/
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      02-28-2018, 05:32 AM   #110
juld0zer
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Has anyone had any success coding off Soft Stop? (SST)?
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