Speedo offset fix...

[wpoll]

Just finished looking at my current IKE data via NCS Dummy.

Firstly, the IKE is listed as KMBI_E38.C12.

Secondly, some of the data in my PA Soft BMW Scanner IKE module binary dump doesn't seem to line up with what NCSDummy indicates.

0x00b8 is Speedometer Offset - value 0f is unlisted - (dec. is 15)
0x00b9 is Speedometer Maximum Value - value 33 = 250km/h (dec. = 51)
0x00ec is Speedometer Offset (Complimentary) - value f0 is unlisted (dec. = 240 - 240km/h?)
0x00ed is Speedometer Maximum Value (Complimentary) - value cc is 250km/h

I'll keep digging through this - got a tiger by the tail!!

[andrewwynn]

Wife's car is off about 3 mph at 80 so that's almost 4%.

Decimal of 15 could be 1.5% almost seems like why bother.

240 could be 2.40? That seems more probable.

What have your measured for the real vs apparent speed on your X5?

Weird on BMW to do this. My other cars mostly had acutlal speed speedometer. I would do timed miles occasionally to confirm my speedo was accurate back in the pre gps days.

[andrewwynn]

Originally Posted by Ohsoslow

How much of an offset are you going for... would be nice to half it.. save $35 every 1000ks

I'm curious about this thought. This offset changes the speedometer display not the odometer. Do you pay by the km that you drive? Entirely too logical of a way to have people pay for the roads they wear out that will never take off in the USA. (people have proposed using GPS in the car but as that would also help prove who causes crashes they have blocked that legislation of course)

[wpoll]

Originally Posted by andrewwynn

I'm curious about this thought. This offset changes the speedometer display not the odometer. Do you pay by the km that you drive? Entirely too logical of a way to have people pay for the roads they wear out that will never take off in the USA. (people have proposed using GPS in the car but as that would also help prove who causes crashes they have blocked that legislation of course)

Ohsoslow and I were making a joke about road tax evasion. Here in NZ roading is paid for by a levy on fuel and when this was introduced (decades ago) when most passenger cars ran on petrol and most agricultural equipment ran on diesel. To avoid penalising farmers this levy was only applied to petrol sales - road users of diesel vehicles pay this levy seperately via a system called Road User Charges. You have to pay in advance for blocks of distance you intend to travel. I usually purchase 5,000km or 10,000km blocks ($312 and $625 respectivily). This once really only applied to the transport industry but with the massive increase in diesel-powered private vehicles, many of us now pay RUC on top of our fuel costs.

And yeah, the coding changes we are discussing don't affect odometer readings.

[wpoll]

Originally Posted by andrewwynn

Wife's car is off about 3 mph at 80 so that's almost 4%.

Decimal of 15 could be 1.5% almost seems like why bother.

240 could be 2.40? That seems more probable.

What have your measured for the real vs apparent speed on your X5?

Weird on BMW to do this. My other cars mostly had acutlal speed speedometer. I would do timed miles occasionally to confirm my speedo was accurate back in the pre gps days.

Setting up to do this today. I have two GPS units and will monitor the "analogue" speedo, the BC speed readout (via the MID) and the calculated V: value (via menu #8).

Here in NZ we have many roadside speedo check signs. They place them on long straight sections of highway, with a information sign to warn you to get ready, then five more signs, exactly 1km apart. Handy....

[e39_touring]

US spec BMW's are coded from the factory with a default 3mph optimistic speedometer. It's 3mph across the board and not a percentage factor. Any additional error is due to variations in tire rolling radius.

It's very easy to change or eliminate the speedo fudge factor using ncs expert. Iirc, you can do up to + or- 6mph/10kph.

[wpoll]

Originally Posted by e39_touring

It's very easy to change or eliminate the speedo fudge factor using ncs expert. Iirc, you can do up to + or- 6mph/10kph.

There's a ton of info for other BMW platforms but I haven't found anything on the e53 - hence this thread.

[e39_touring]

It's the same for e53. Are you just looking for a step by step instruction on how to change it? I am only familiar with ncs expert but not the other tools that purportedly can individualise our cars.

[Overboost]

Originally Posted by wpoll

Just finished looking at my current IKE data via NCS Dummy.

Firstly, the IKE is listed as KMBI_E38.C12.

Secondly, some of the data in my PA Soft BMW Scanner IKE module binary dump doesn't seem to line up with what NCSDummy indicates.

0x00b8 is Speedometer Offset - value 0f is unlisted - (dec. is 15)
0x00b9 is Speedometer Maximum Value - value 33 = 250km/h (dec. = 51)
0x00ec is Speedometer Offset (Complimentary) - value f0 is unlisted (dec. = 240 - 240km/h?)
0x00ed is Speedometer Maximum Value (Complimentary) - value cc is 250km/h

I'll keep digging through this - got a tiger by the tail!!

Found this on the E39 Bimmerforums

This is an excerpt from another post with some additions.
I take no responsibility for anyone messing around with his/her software without knowing exactly what they are doing!

Open PASoft and go to IKE, read eprom and backup. Do a search for consecutive values 11, 33 and values EE, CC

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.

Some E39's have two copies of its data and the second set, which also must be changed, they should be at addresses 0260, 0261 and the complement data at 0294, 0295.

If you get those values at different addresses or a excessive number then you will need to use NCSExpert to verify the correct address. My IKE is an older software version and only had one copy.

https://www.bimmerforums.com/forum/s...5#post29859785

[andrewwynn]

Originally Posted by wpoll

Setting up to do this today. I have two GPS units and will monitor the "analogue" speedo, the BC speed readout (via the MID) and the calculated V: value (via menu #8).



Here in NZ we have many roadside speedo check signs. They place them on long straight sections of highway, with a information sign to warn you to get ready, then five more signs, exactly 1km apart. Handy....

In the USA most freeways are marked every mile. Recently they added 1/10th in the cities. Makes it very easy to request help by mentioning the mile marker where you broke down.