Thanks for all the additional info. but I've spent way too much time researching this already and have read most of the e38/e39 stuff on this.

So far it doesn't seem the same on the e53 - or at least on mine. Very similar but not quite the same....

The max speed on these vehicles is governed to what the factory tires where rated for so you might run into those numbers as well and might add some confusion. I would imagine that would be stored in the DME but you never know! Good on you for taking this on though! :bow:

I have the same KMBI_E38.C12 cluster in mine. I opened my TRC file from my cluster and from my reading to get an accurate speed value just change the settings in the 4 addresses listed to the Japanese variant in NCS Expert.

The two bytes for speedo calibration and scale length should be at addresses 00B8, 00B9 are 11, 33. Changed to 09, 3C to select Japanese (accurate) speedometer.

The complemented data that should be at addresses 00EC, 00ED are EE, CC. Changed to F6, C3. (Also Japanese listing)

Japan is the one country BMW left as precise from all my reading.

That being said, I really have no desire to change mine, I kinda need the buffer. I am always targeting +8MPH over the posted speed limit and that puts me at +5MPH over.

Likewise when I noticed the showed was off 3-4 I didn't even tell my wife who tends to drive a little fast but she figured it out. That said she still will drive say 5-8 over which becomes 2-5 over which is very safe from cop radar point of view


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Thanks Overboost. This is the same info I've been reading but it seems it doesn't apply to my car. You've seen the values I've posted for those four data fields and the settings that control these AREN'T in my current trace file. At all. They are all listed in NCSDummy but no value is selected and everything is greyed out... :dunno:

I've also read that just changing these four hex values (assuming they apply to your car) while achieving the desired result also results in an IKE checksum mis-match, so I think we would need to locate and adjust the checksum value if changing the hex data values. Maybe that's only an issue if you change the raw hex via BMW Scanner rather than changing the value via NCS Expert/NCSDummy. :dunno:

I'm going to get some GPS speed readings later on today so I can verify what my car is actually doing. Like you, I'm not actually worried about changing this - I just want to figure out how too - for those folk out there that DO want to change it! ;)

The current grace speed in NZ is 4km/h over i.e. 105km/h on a highway (or 55km/h in a town etc.) will get you a speeding ticket and demerit points.

Three speeding tickets within two years will cost you your license.... :yikes:

Here's what I see in NCSDummy...

http://i67.tinypic.com/34dogaq.jpg

and

http://i65.tinypic.com/zxtt9k.jpg

I've verified that the text itself does not appear in the trace file either.

I know it's no problem to add the parameter and set a value - but I wonder how my car is currently configured, given I know it's displaying off-speed but not because of these settings! :confused:

Mine were grayed out too but once you select one of the selections, it becomes active. I think if there is no offset change from factory, it is not active in NCS.

As far as the checksum goes, I think that is only when using BMW Scanner. Changing this in NCS should take care of itself. :dunno:

Should be easy to test. 4 check boxes and send... At worse, if it doesn't work right, remove the check marks and resend.

OK, that make more sense. So your 3.0i is the same as my 3.0d. The e38/e39 folk indicate that on those platforms the setting IS active, so changing it is a valid move.

It seems on our platform something else may be going on but like you said, it's easy to test.. gulp..:thumbup:

For sure it's nice to understand whats going on and having control and the option to make changes is a bonus! Good information and a good learning experience overall. :)