F10 Disabling speed "KORREKTUR" -- success anyone?

Greetings fellow coders.

I haven't been able to get the analog or digital speedometer to display uncorrected (accurate) values on my 2013 F10 M5. Still showing +3 mph at speeds over 60 mph as compared with my handheld GPS.

Per the cheat sheet v3, I changed "KOMBI 3000 Anzeige_Konfiguration BC_V_KORREKTUR" to nicht_aktiv aktiv / Werte=01 but that hasn't done the trick.

Any thoughts?

You say it's +3mph now compared to your gps. How much was the difference before changing the value?

I don't know that comparison to GPS is relevant. It is supposed to correct the Analog speedometer reading. How does the dial speedometer compare now to the digital speedometer in the BC Cluster assuming you enabled it with BC_DIGITAL_V = aktiv. I would expect a slight difference in the two after coding BC_V_KORREKTUR.

On the E series there was a correction of 5mph...I would think this would hold true for the F series also

Many thanks for the replies. The values stayed the same after coding.

FYI-- My display has the large digital speedometer underneath the analog gauge next to the time. Coding the BC to add the digital speedometer displays a second, smaller digital speedometer to the mutli-display at the bottom of the speedometer circle (where the mpg, range, date, etc. are displayed).

All three are in sync and remain in sync with the Korrektur coded to activ or nicht activ.

Anything else to try?

Originally Posted by mhercz

Many thanks for the replies. The values stayed the same after coding.

FYI-- My display has the large digital speedometer underneath the analog gauge next to the time. Coding the BC to add the digital speedometer displays a second, smaller digital speedometer to the mutli-display at the bottom of the speedometer circle (where the mpg, range, date, etc. are displayed).

All three are in sync and remain in sync with the Korrektur codes to activ or nicht activ.

Anything else to try?

Ah yes, you have an M5, so you have the large Digital MPH readout already.

What if though BC_V_KORREKTUR is correcting all three readouts? Is it the same +3 over your GPS speed before and after coding?

Yup, the analog and both digital speedos read the same when the Korrektur is coded to activ vs. nicht activ: +3 at 60 mph measured against GPS. So it would seem the Korrektur isn't doing anything.

Originally Posted by mhercz

Yup, the analog and both digital speedos read the same when the Korrektur is coded to activ vs. nicht activ: +3 at 60 mph measured against GPS. So it would seem the Korrektur isn't doing anything.

Strange. I don't know.

Just found a CAF in HC2 that seems related: 3000 HC2_Codierdaten, 04 under Funktionen Korrekturkennline. The options are for various F models, and there's one option for Anlieferzustand. Any idea what this is?

Originally Posted by mhercz

Just found a CAF in HC2 that seems related: 3000 HC2_Codierdaten, 04 under Funktionen Korrekturkennline. The options are for various F models, and there's one option for Anlieferzustand. Any idea what this is?

I don't know. My F10 doesn't have an HC2 module.

Looking at cafd_00000160.caf.003_004_010 though, the comment and translation is:

Kommentar=Parameter legt fest, welche Korrekturkennlinie verwendet wird.
Comment = parameter specifies which correction curve is used.

The question remains, a correction of what?

Mysterious. I'll try coding it various ways and see what happens.

Leads me to wonder if there's an official BMW coding manual floating around somewhere . . .

Originally Posted by mhercz

Mysterious. I'll try coding it various ways and see what happens.

Leads me to wonder if there's an official BMW coding manual floating around somewhere . . .

There is I am guessing. It is probably heavily guarded, on a red velvet pillow under a glass dome in Munich though.

Requiring a pouch filled with sand of equal weight to fool the booby traps . . .

...someone cue up the theme to Mission Impossible and buy mhercz a plane ticket to Munich...

Hi, same here. I also am trying to reduce the notorious german car speedometer overestimation error. On my 2013 F25 X3, it's about +3-4%. I am sure that it must be a simple and hidden coding parameter : X3 are used by law enforcement agencies and I bet that their speedos are dead on !

My issue is a little worse since I installed (voluntarely) slightly smaller circumference winter tires :-(

I have tried both settings on bc_v_korrektur with no noticeable difference, analog or digital...

Originally Posted by mhercz

Greetings fellow coders.

I haven't been able to get the analog or digital speedometer to display uncorrected (accurate) values on my 2013 F10 M5. Still showing +3 mph at speeds over 60 mph as compared with my handheld GPS.

Per the cheat sheet v3, I changed "KOMBI 3000 Anzeige_Konfiguration BC_V_KORREKTUR" to nicht_aktiv aktiv / Werte=01 but that hasn't done the trick.

Any thoughts?

Just to let you know that in new F30 for NA the bc-v-korrektur is aktif by default and it shows +3mph

Originally Posted by dromader

Just to let you know that in new F30 for NA the bc-v-korrektur is aktif by default and it shows +3mph

Yes. aktiv is the default, and it means that BMW is correcting the speed. In this case, you want to disable it, so nicht aktiv is what is needed for true uncorrected speed.

Aha I get it corrected means adding 3mph ... I'll try deactivate and see what happens

Aha I get it corrected means adding 3mph ... I'll try deactivate and see what happens

Did coding the Korrektur to "nicht activ" make the +3 mph go away for you?

Haven't have time yet, I plan to try it tomorrow or Friday ... I'll let you know if it works.

I tried it but I see no difference

I'll let the car sleep overnight and plug in my Garmin and compare

Any luck?
Got to think the Korrektur code does something, so maybe we're missing another code.

In another thread recently somebody enabled the digital speedometer in addition to disabling the speed correction. Maybe that's the trick. I'm stuck in the house waiting for Santa , once he comes we're taking a 100 miles trip perfect to test if disabling the speed correction did anything

One thing I never searched if the correction is + 3mph or +5%

Originally Posted by dromader

In another thread recently somebody enabled the digital speedometer in addition to disabling the speed correction. Maybe that's the trick. I'm stuck in the house waiting for Santa , once he comes we're taking a 100 miles trip perfect to test if disabling the speed correction did anything

One thing I never searched if the correction is + 3mph or +5%

On the E60 you had both as follows:

BC_V_KORREKTUR = Correction for Analog speed
BC_DIGITAL_V_KORREKTUR = Correction for digital speed

BMW can advance the speedometer by 10% + 2.4 MPH per the attachment, which at higher speeds can be pretty substantial. 90 MPH could read as high as 101 MPH.

I'm at the same point (2013 M5).

SpeedometerS are at 74 when going 70.
Adjusting the one BC_V_KORREKTUR key that I found had no effect.

Could not find any others that seemed relevant.

Moving to a 295/35 on the rear is enough to offset the 4% but would prefer a software solution as opposed to hardware purchase.