|
|
|
02-07-2017, 06:58 PM | #90 |
Lieutenant
225
Rep 542
Posts |
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 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)
__________________
Last edited by dbronnik; 02-08-2017 at 03:54 PM.. |
Appreciate
3
|
04-02-2017, 04:54 PM | #91 |
Lieutenant Colonel
480
Rep 1,600
Posts |
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? |
Appreciate
0
|
04-03-2017, 11:24 PM | #92 | |
Lieutenant
225
Rep 542
Posts |
Quote:
Also it wouldn't do anything to disable FBS, FLR or BB_RAB since those don't need any yaw data.
__________________
|
|
Appreciate
0
|
04-09-2017, 04:54 PM | #93 |
Lieutenant Colonel
480
Rep 1,600
Posts |
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 |
Appreciate
0
|
06-12-2017, 07:50 AM | #94 |
BMW Fan
294
Rep 847
Posts |
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.
__________________
2012 135i Mods: air scoops, CP, K&N filter, PS1, ADE FMIC, BMW PE, JB4, 1M front body, full M3 suspension front and rear, M3 brakes front and rear, M3 rear subframe and LSD
Owned so far: 88 M3 x 2, 95 325is, 95 M3 x 2, 06 Mini Cooper S, 08 335 xi, 09 Z4 35i, 01 M3, 12 135i |
Appreciate
0
|
06-15-2017, 11:26 AM | #95 |
First Lieutenant
84
Rep 341
Posts |
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.
|
Appreciate
0
|
06-15-2017, 11:30 AM | #96 | |
First Lieutenant
84
Rep 341
Posts |
Quote:
|
|
Appreciate
0
|
06-16-2017, 04:51 PM | #97 |
Private
10
Rep 66
Posts |
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. |
Appreciate
1
cerealwars161.00 |
06-16-2017, 05:07 PM | #98 | |
Private
10
Rep 66
Posts |
Quote:
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.. |
|
Appreciate
0
|
06-16-2017, 05:46 PM | #99 | |
First Lieutenant
84
Rep 341
Posts |
Quote:
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.. |
|
Appreciate
0
|
07-08-2017, 10:28 PM | #100 |
First Lieutenant
84
Rep 341
Posts |
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. |
Appreciate
0
|
07-11-2017, 10:03 AM | #101 | |
Private
10
Rep 66
Posts |
Quote:
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. |
|
Appreciate
0
|
07-11-2017, 10:30 AM | #102 | |
Major
429
Rep 957
Posts |
Quote:
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.. |
|
Appreciate
1
AndyW697.00 |
07-11-2017, 11:01 AM | #103 | |
Major
429
Rep 957
Posts |
Quote:
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. |
|
Appreciate
0
|
07-14-2017, 01:13 AM | #104 | |||||
Private
10
Rep 66
Posts |
Quote:
Quote:
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:
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:
Quote:
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. |
|||||
Appreciate
0
|
07-14-2017, 08:53 AM | #105 | |
Major
429
Rep 957
Posts |
Quote:
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.. |
|
Appreciate
1
cerealwars161.00 |
08-30-2017, 06:53 AM | #106 | |
Lieutenant Colonel
480
Rep 1,600
Posts |
Quote:
|
|
Appreciate
0
|
09-13-2017, 07:17 AM | #107 | |
Lieutenant Colonel
480
Rep 1,600
Posts |
Quote:
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. |
|
Appreciate
0
|
02-13-2018, 04:47 PM | #108 |
Second Lieutenant
27
Rep 255
Posts |
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. |
Appreciate
0
|
02-14-2018, 06:13 AM | #109 | |
Second Lieutenant
79
Rep 237
Posts |
Quote:
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/ |
|
Appreciate
0
|
Post Reply |
Bookmarks |
|
|