Speed signal direct MSS54 - DSC removal

[NZ_M3]

Hi all

Just wanting to see if anyone has actually done this and what they did in terms of speed signal direct to pin 22 on x60004?

Have been working on an odd car that isn’t quite right wiring wise and we’ve programmed out speed signal from DSC to direct and removed dsc all together. The wheels speed sensors are still in place and of course if you unplug the dsc the car goes into limp mode. It has no LWS and no yaw sensor either (it is a racecar) We’ve gotten around Limp mode by adjusting the limp map but just wondering what people have done to remove dsc completely from the vehicle? DSC is programmed out of the dme also.

I guess the question is how is the speed signal processed when it Set as direct?

[Cristov9000]

People who do engine swaps into older BMW chassis use the signal from the diff that speedo runs off of. There is some coding changes for the ECU for it to calculate pulses per mile.

[NZ_M3]

People who do engine swaps into older BMW chassis use the signal from the diff that speedo runs off of. There is some coding changes for the ECU for it to calculate pulses per mile.

Yes I know all these but haven’t seen anything definitive on an e46 chassis and I’ve tried a few things already similar to the E30 and E36 swap and it doesn’t seem quite right.

[S54B32]

You need diff or wheel sensor. Otherwise it‘s not possible to calculate speed (but maybe GPS can be an option). If you use diffsensor (but in e46 m3 Diff case very difficulty) you can let MSS54 calculate wheelspeed.
otherwise DSC is needed for wheelspeed. Btw near every racecar this day has abs Modul. And MK60 is a fantastic race abs! Only other option beside these 2 is to read one abs sensor with selfbuild microcontroller and write it to Can for OEM cluster.

[SliM3]

If you just don't want DSC intervention you can lock it out of torque management.
Set K_MD_ASC_CONTROL to 01 = ASC LOCKED and K_MD_STAT_ASC to 03 = ALL INTERVENTIONS REFUSED.

[NZ_M3]

If you just don't want DSC intervention you can lock it out of torque management.
Set K_MD_ASC_CONTROL to 01 = ASC LOCKED and K_MD_STAT_ASC to 03 = ALL INTERVENTIONS REFUSED.

Have done all that already.

The car runs no dsc module as it has a pedal box but we’ve had to leave the dsc computer plugged into the loom for signal processing otherwise the car does some strange things even with limp map adjusted.

Basically speaking the noise from it at high revs from the lack of a processed speed signal causes the vanos to act strangely and the car loses torque.

we are trying to trace and see if it is a wiring issue or we need to build something for the speed signal so the dme can function correctly and just want to see if anyone has done anything with the e46 chassis similar that got around the issue?

[Nergdnvlt]

If you just don't want DSC intervention you can lock it out of torque management.
Set K_MD_ASC_CONTROL to 01 = ASC LOCKED and K_MD_STAT_ASC to 03 = ALL INTERVENTIONS REFUSED.

If you do this - does the DSC light come permanently on? My DSC light is permanently on (No ABS light, or trifecta), I throw no codes whatsoever (abs sensor, dsc sensor, yaw etc), have checked all ABS/DSC fuses. And I actually like not having DSC - I would just like to know why my car is like this. Ha.

[SliM3]

Most likely CAN timeout causing the permanent lamp. Normalized torque value is still being sent via CAN to the DSC unit to control engine braking (MSR).

[flm]

Hi!

Has anybody found any solutions for DSC delete? What will the limp mode look like, when caused by missing DSC? I have a similar problem- s54 swap, have no DSC (have a fault code active), but have used some bin modification tool that supposedly removed "dyno rpm limit"(=can set dyno rpm limit manually to 8000rpm) and I also use road speed emulator(if activated, DME sees around 50kmh road speed constantly). No other modules from stock M3 but MSS54 DME. The problem actually is that I only have around 230 rwhp on dyno. Peak torque around 5000rpm is only 220fl/lbs and 170ft/lbs at 7000rpm. The torque curve looks similar to other stock s54 dyno graphs(max torque around 5000rpm), but numbers are low. Can be a lot of other things as well, but started the easy way and checked fault codes again- only active fault that might cause this is DSC missing (road speed not missing). If someone can confirm that it is not caused by missing DSC, then I can continue finding the problem elsewhere.

[flm]

Ok, changed tweaked with this "dyno mode" rpm limit and found out that the car is still in this limp mode that anybody calls "dyno mode" that has stock rpm limit at 6300 I think. Can someone confirm that only thing limited in this "dyno mode" is rpm and raising it to 8000+rpm will be using the same fuel/ignition/vanos maps as regular mode?

[flm]

Ok, tested again and activated real dyno mode with GT1 and DIS and the rev limiter is raised to normal limit and the car sounds and feels different. Will do dyno run on rollers, but it probably shows that if swapping the engine without DSC, raising the rev limit with MSS54Binary tool in "Dyno mode rev limit" is actually some kind of a limp mode rev limit and raising it will give you 8000rpm but not full torque. So the question is how to permanently keep this dyno mode active with coding? Then you probably do not need DSC at all, but this has to be verified on dyno.

[S54B32]

Any updates on this? Planning to install the CSL software on a friends s54 e30. Is the dme without dsc in limp mode?

how swap people deal with this? Prevent the limpmode somehow or adjust limp vanos and limp „AlphaN“ maps?


edit:
maybe parameter: Operational Mode_Dyno can help.

Standard is: 0-„FZ betrieb“ (vehicle Mode). Also possible are 1-„Prüfstand“ (engine Dyno) and 2-„Rolle“ (Normal car Dyno)

[flm]

No update as winter came, dyno was too far away and had no grip for road testing any more (only excuses ) Felt better with dyno mode enabled but it was wheelspin most of the time and gave no real comparison. This parameter is good find. I have to figure out how to read my car with NCS Expert as I have nothing but ECU connected. Or change parameters some other way as my friend can read over bdm. But as it is winter, I have my turbo e36 project active and can work on my e30 in April probably when the snow is gone. But if you figure out something before, keep everyone updated. Just to remind you that it is still possible that I have some other problems and the missing power is not because of DSC missing. Good luck with the swap!

[BMWfanz]

No update as winter came, dyno was too far away and had no grip for road testing any more (only excuses ) Felt better with dyno mode enabled but it was wheelspin most of the time and gave no real comparison. This parameter is good find. I have to figure out how to read my car with NCS Expert as I have nothing but ECU connected. Or change parameters some other way as my friend can read over bdm. But as it is winter, I have my turbo e36 project active and can work on my e30 in April probably when the snow is gone. But if you figure out something before, keep everyone updated. Just to remind you that it is still possible that I have some other problems and the missing power is not because of DSC missing. Good luck with the swap!

Hi! You need to change this 2 parameters:K_V_control 0 k_v_wiegimpulszahl 4749

[Jony787]

Are the following DTCs disabled?
131: DTC DSC intervention implausible
132: DTC CAN timeout, DSC
133: DTC CAN timeout, Steering Angle Sensor



The famous Dyno Rev Limit map is in fact K_N_MAX_VFEHLER
Max RPM with speed input error.

In my e36 compact S54 SMG swap I feed vehicle speed from the oem e36 abs so my K_V_CONTROL equals 2= Speed from ASC. A value of 0 equals Direct. Any other value means UNDEFINED. Keep in mind that with K_V_CONTROL=0, DME is still expecting a signal. You need to disable DTCs in order to prevent the DME from acting up on such codes.