Mph to kph conversion for Subaru EMCD

[Gerald81]

I'm using the plug and play Subaru EMCD and GVW4, and noticed that although the wheel speed RPM axis in the active tables are represented as "kph", they actually work in "mph". For example, if my actual speedometer is showing 100kph, the active table is shown as using the lock settings for "60", which I presume is represented in mph despite the axis labels reading "kph". Can anyone advise on how I can convert them into kph? Thanks!

[R!C0]

All the calculations are done in KPH in the ECU. The fact it is not reading correctly suggests it is not interpreting the data from the wheel speeds correctly. Check check the following options: WhlCircm (Tyre circumference), WhlTeeth (teeth on the wheel speed sensor).

[Gerald81]

When I monitor the live data parameters from the four wheel speed sensors and vehicle speed output, they appear to be reading in KPH correctly. I have set the WhlCircm (195) and Whlteeth (0) accordingly to ensure that all four wheel speed sensors are consistent with the readings from my car's speedometer.

However, when monitoring the active table grids, the vehicle speed on the Y-axis appears to be working in MPH. In other words, when the four wheel speed sensors reflect "100" KPH (as does my speedometer), the active table grid is taking readings of differential lock from the "60" KPH plot on the Y-axis.

[R!C0]

So the parameter Wheel Speed reads correctly?

What does LFspd read when you are at 100kph?

[Gerald81]

It reads 100 KPH, exactly the same as my speedo. The problem appears to be that the wheel speed axis table is denominated in MPH, even though its units are reflected as KPH. For example, if I define my wheel speeds as 0,30,60,90,120...210, it appears that these are in MPH. Which is why when I'm travelling at 100 KPH (speedo and wheel speed parameter), the active map is only using the lock specified for 60.

[R!C0]

OK we've investigated this and it looks like an error with the GIN file. The EMCD is quite old code and does not have configurable units. It looks like that axis is not referencing the correct value for wheel speed, is instead referring to a intermediate value, which just happens to look like an MPH value.

Very surprised by this as this code has been out for many years.

We will work on getting a new version out. in the mean time I'm afraid you will have to offset your tables accordingly.

Apologies for this and we try to resolve it soon.

Regards

Rico

[Gerald81]

What is this intermediate value that the active tables are referring to, if it is not in mph format?

I also noticed that my slip, FAspd and RAspd outputs are throwing up some very strange live numbers (1000+) when on the move, even though my individual front and rear wheel speeds appear correct.

Approximately when do you expect to get this issue resolved?

[R!C0]

The value is internal and not accessible, hence the problem.

Are the slip values momentarily off or consistently? Sometimes noise coming from the wheel speed sensors can throw the slip value off for a split second.

Not sure how long this will take to fix, it is currently being looked at.

[Gerald81]

The FAspd, RAspd and slip values are consistently off, i.e. consistently reading in the thousands. The four individual wheel speeds and overall vehicle speed values are working fine.

Do you still have a copy of the GIN file I sent to you recently?

The GIN file I downloaded off your website did not allow me to change the RPM step parameter for defining the Y-axis (slip) of the active tables. For example, regardless of any RPM step value I entered, the axis will always remain as 0,1,2,3,4.

The GIN file I am using is provided by my local reseller and works correctly for the RPM step adjustment. However, both GIN files do not work correctly in terms of the X-axis of the active tables, as well as the FAspd, RAspd and slip values.

I hope you can fix this asap so I can continue working with the differential controller maps.

[Gerald81]

Just an update, I've tested it again and found that the slip values appear to be working normally, it is just the FAspd and RAspd values that are off. They are throwing up numbers in the thousands while moving, while the individual wheel speed and slip values are normal. When stationary, all values (wheel speeds, vehicle speed, slip, FAspd and RAspd) are 0.