Simulate DSC Speed Signal

Hello.

I hope we can find help here.

We installed a motor from a BMW 123D (N47S) into an E46 for racing purposes.
Now we have the following problem: the engine cuts out at 3900 RPM.

We have already determined that the Digital Drive Encoder (DDE) is missing the rear axle wheel speed signals because we did not install Dynamic Stability Control (DSC).

Can someone emulate these signals?

We have installed a motorsport ABS system that outputs speed information using a square wave signal. Is it possible to convert this signal? We don't have the time to become CAN bus specialists.

Thank you.

Hi,

What does the speed square wave signal look like exactly? An electronic circuit that interprets this signal and sends corresponding CAN messages would be relatively easy to implement, provided you know which CAN messages are expected.

Best regards, Rainer.

Hi.
Okay, we will be measuring the rectangular signal.

The issue with the expected CAN messages is a problem, and we have no idea what's causing it.
We've already determined that this error occurs as soon as you disconnect both of the rear ABS sensors on a standard production vehicle.

Greetings.
Fritz.

In this case, I would consult a reputable chip tuner (one who writes their own software).
If they don't live too far from the Netherlands, I might know some tuners in the Netherlands who can do that.

We've already been to Tuner.

At first, the response was always "yes, yes, no problem."

After several hours of clicking around, I always got the same answer: with the previous model or with vehicles from VW Group, it worked; but not with ours, because apparently this signal is used in multiple modules.

We're not experts ourselves, so we have to just take their word for it.
That's why the idea of an emulator came about.

I didn't want to say anything, but I think it definitely won't be as simple as just clearing the corresponding error message in the engine control unit.

You should be able to find some information about wheel speed signals and the speed data that the ABS system puts on the CAN bus at VAG (Volkswagen Group). Unfortunately, I have no idea how it's implemented in BMW.
If a chip tuner has a description file for the specific engine control unit (ECU), they may be able to examine it to see which CAN IDs are expected and what values they should contain.
Alternatively, you can find an identical ABS control unit on the used parts market (e.g., eBay), and then use KCANMonitor to log which CAN IDs it transmits.

Best regards, Rainer.

CAN-Diagnose wrote:

I didn't want to say anything, but I think it definitely won't be enough just to simply delete the corresponding error message in the engine control unit...

You need a tuner that can do more than just increase fuel and turbo boost.

muurman wrote:

CAN-Diagnose wrote: I didn't want to say anything, but I think it definitely won't be as simple as just clearing the corresponding error message in the engine control unit... You need a tuner that can do more than just increase fuel and turbo boost.

Do you have any overview of relevant datasets that would allow me to assess what is specifically needed for his control unit?

CAN-Diagnose wrote:

muurman wrote: CAN-Diagnose wrote: I didn't want to say anything, but I think it definitely won't be as simple as just clearing the corresponding error message in the engine control unit... You need a tuner that can do more than just increase fuel and turbo boost. Do you have any overview of relevant datasets that would allow me to assess what is specifically needed for his control unit?

I'm not sure, but maybe a good tuner could. But this is just my thought. I'm not certain.

I haven't been involved in car tuning for a while. For example, if you replace a pressure sensor, the values need to be reprogrammed in the ECU.

Fuel is limited in several places/data points within the ECU. I believe the approach would be to search all maps within the ECU software where fuel is restricted, and then identify those that utilize the DSC sensor.