[Guide] [T6_modified] T6 Speedo Adjustment with VCDS

[mmi]

Thanks. Interesting
Obviously you tried coding both ways:
1) more intuitive user interface: Wheel circ - Version, and
2) coding directly into byte 3 (82, 87)
For the latter did you try to go first into "Security access" and then into Long coding?

Here is a scan of a T6.1 with the same dash cluster. However, not sure if it helps at all.​

T6.1 New model

Wednesday,01,January,2020,14:35:16:43540 VCDS -- Windows Based VAG/VAS Emulator Running on Windows 7 x64 VCDS Version: 19.6.2.2 (x64) HEX-V2 CB: 0.4508.4 Data version: 20200210 DS308.0 www.Ross-Tech.com VIN: WV2ZZZ7HZLH032678 License Plate: T6.1...

forums.ross-tech.com

​

 

[mmi]

VW Transporter T6.1 2021 Wheel size coding changes issue

Hiya folks! A customer of mine changed his wheels to 20" and wanted his speedo coded to suit the new wheel size. No issue as this is an available change via the "K-Number" coding in 17 Instrument Cluster and done this many times in older Transporters and Amaroks. Well, turns out there is an...

forums.ross-tech.com

EDIT:
Not T6.1 but the same MQB platform as T6.1 - also irreversible on Crafter

2020 MAN TGE (VW CRAFTER2), Coding BYTE3 in Control Unit J285 can not be undone

Hello VCDS community, first I have to thank Uwe for this great tool (VCDS), which gives me so many opportunities with the car. I love it. Thank you very much for that. :thumbs: A short introduction to my person. My name is Thorsten and I am an electronic engineer and computer guy from Germany...

forums.ross-tech.com

 

[foggy3061]

I was in my own van with the VCDS (for a change) and though i'd gather my speedometer data while i was there, just for info.

 

[robmug]

Hi all, can you use Carista to change this setting, or must it be VCDS?

Its the only change I need to make, and want to do it the simplest way.....

Thanks
Dean

Did you manage to change it with Carista?

 

[Glenn Board]

no, had to use VCDS

 

[peteslack]

I used VCDS too got my speed to within one mph at 70 - improved the mpg too...

 

[JimmyAK]

I'm looking to do this to my new 22 plate T6.1 Startline that has had the original steel wheels swapped out and is now running on 275/40/20's. The speedo is reading about 5mph low @70mph, so I was very happy when I found this thread. I am trying to follow the excellent walkthrough that @mmi posted, but it looks like things may have changed a bit since it was written. I don't know whether that's down to a more recent version of VCDS or the VW software.

When I search for the 'IDE0084' values, the K-number (IDE00842) doesn't appear. Instead there's just two different IDE00845 values.



And if I look at the long coding helper I get this drop down list for Bit 0-2.



So I'm thinking that changing this would alter the wheel circumference? I don't want to screw anything up though, so has anyone else done this recently and seen the same result?

 

[racerke600]

Yes you can alter this. But be aware this can only be altered from a lower to a higher variant. It's irreversible!!!

 

[JimmyAK]

That's worrying. Makes it a risky change! Has anyone set variants 2+ and can tell me what the new circumference values were?

 

[mmi]

things may have changed a bit since it was written. I don't know whether that's down to a more recent version of VCDS or the VW software.

The thread is about T6.
T6.1 is electrically/electronically very different vehicle. As @racerke600 mentioned still not known how to revert coding if needed.

 

[Lightrofit]

The thread is about T6.
T6.1 is electrically/electronically very different vehicle. As @racerke600 mentioned still not known nhow to revert coding if needed.

And it’s still not known now sadly.

When I fell foul of the one way coding, I was more fortunate than most to have my ODIS with me and even ODIS refused to revert the coding back to factory, no matter which way I tried.

I have emailed VW technical and had no reply so didn’t pursue that direction.

It will eventually become an issue at the dealerships so a TPI will be released either with an SVM or SW update or SVM for a SW update but I’ve not had a T6.1 recently enough to check for any TPI updates.

 

[racerke600]

Indeed ODIS doesn't work either. I tried with a second hand instrument cluster. But that didn't work.
T6.1 won't accept a second hand cluster with another car coded to it already.

Only solution is to buy a brand new cluster, and have that recoded to factory settings.

I find it hard to believe that VW isn't aware of this 'issue'. My guess it has something to do with tacho fraude.
But there should be some kind of workaround to reset it back to factory settings , hence you're not doing anything wrong imo.

My ACC is buggy in 5th gear, so I skip this one if I wan't to use ACC.
And start/stop isn't working once i engage 5th gear. (doesn't bother me).

If only someone technical from VW with knowledge of this matter could explain how & what?

 

[Lightrofit]

Indeed ODIS doesn't work either. I tried with a second hand instrument cluster. But that didn't work.
T6.1 won't accept a second hand cluster with another car coded to it already.

Only solution is to buy a brand new cluster, and have that recoded to factory settings.

I find it hard to believe that VW isn't aware of this 'issue'. My guess it has something to do with tacho fraude.
But there should be some kind of workaround to reset it back to factory settings , hence you're not doing anything wrong imo.

My ACC is buggy in 5th gear, so I skip this one if I wan't to use ACC.
And start/stop isn't working once i engage 5th gear. (doesn't bother me).

If only someone technical from VW with knowledge of this matter could explain how & what?

That’s interesting, I haven’t had the chance to play about with a used cluster on a 6.1 to match one but that’s the first I’ve heard of any VWAG vehicle rejecting a used cluster.

I wonder if this is a sign of things to come for future vehicles.

 

[Big.mac]

Is there anyone in the Portsmouth area that has VCDS and can do this adjustment on my van please? My speedo is under reading by 3-5mph and having recently got one ticket I‘d like to avoid any more….

 

[JimmyAK]

Still wrestling with this and scouring Google for someone who has done it successfully on a T6.1. There's definitely quite a few threads on various forums about people who have got stuck with an incorrect value. Anyway, I decided to take the plunge and start incrementing my variant value, but I've fallen at the first hurdle. Attempting to change from the current value of variant 1, to variant 2...



Hit 'Do It!' and I get this error.



My first guess is that variant 2 isn't compatible with my van and I'll just have to move onto variant 3, 4, 5 etc. until I find one that is accepted. However I'm a total newb when it comes to VCDS, so I chickened out and left it alone. Thought I'd come back here and get some more experienced opinions!

 

[JimmyAK]

Despite lots of searching, I never did find anyone who'd documented this on a T6.1 (or at least posted about it). So I got brave (or foolish) one evening and decided to try it regardless and finally... success! So thought I'd come back here and post my results in the hope it helps somebody else out.

So as a reminder, my conversion was based on a 22-plate T6.1 Startline (T30 150 DSG) with optional business pack. So the OEM wheels were 16 inch steels with 205/65 R16 tyres. As posted previously, the K-number (IDE00842) doesn't seem to exist on the T6.1 and instead there's just two different IDE00845 values, one for trip distance (2066mm) and one for speed (2149mm).



When I looked at the long coding helper I could see my wheel circumference was set to variant 1 - makes sense given the 16" steels are probably the smallest wheels fitted to the T6.1 out of the factory.

So with my 275/40/20's fitted, the speedo is reading ~4mph low at 70mph (speedo = 66mph, measured GPS speed = 70mph) which is pretty much in line with what willtheyfit.com tells me.



Now the scary part. There's plenty of evidence on various forums and in this thread that changing the wheel variant on the new T6.1 platform is a one-way street. i.e. you can increase the variant but not go backwards. So my approach was to increment the variant one step at a time, hoping they scaled in a relatively linear fashion.

Step 1 - set to variant 2. Coding was rejected (Request out of range).



Step 2 - set to variant 3. This time coding was accepted, and my IDE00845 values were increased to 2111mm / 2195mm respectively.



A quick test drive confirmed my speedo error was reduced to about 2-3 mph.

Step 4 - set to variant 4. Coding was rejected (Request out of range).

Step 5 - set to variant 5. Coding was rejected (Request out of range).

Step 6 - set to variant 6. Coding was accepted, and my IDE00845 values were increased to 2195mm / 2294 mm.



Another test drive and now my speedo is pretty much bang on. At this stage I was very happy to call it quits. Whilst I could have tweaked it higher so that the speedo reads a little higher than actual (as is common practise), I wasn't willing to risk a large leap in circumference knowing that I couldn't revert back. Incidentally I did try going backwards just to verify, and can confirm you get 'Coding Rejected Error 22' which prevents you from doing so.

Thanks to everyone who chipped in with advice, particularly 'AudiGit' on the Ross-Tech forums (where there's a similar thread to this) who gave me sufficient confidence to go for it!

I hope this helps out anyone looking to do a similar tweak.

 

[Lightrofit]

Despite lots of searching, I never did find anyone who'd documented this on a T6.1 (or at least posted about it). So I got brave (or foolish) one evening and decided to try it regardless and finally... success! So thought I'd come back here and post my results in the hope it helps somebody else out.

So as a reminder, my conversion was based on a 22-plate T6.1 Startline (T30 150 DSG) with optional business pack. So the OEM wheels were 16 inch steels with 205/65 R16 tyres. As posted previously, the K-number (IDE00842) doesn't seem to exist on the T6.1 and instead there's just two different IDE00845 values, one for trip distance (2066mm) and one for speed (2149mm).

View attachment 159451

When I looked at the long coding helper I could see my wheel circumference was set to variant 1 - makes sense given the 16" steels are probably the smallest wheels fitted to the T6.1 out of the factory.

So with my 275/40/20's fitted, the speedo is reading ~4mph low at 70mph (speedo = 66mph, measured GPS speed = 70mph) which is pretty much in line with what willtheyfit.com tells me.

View attachment 159452

Now the scary part. There's plenty of evidence on various forums and in this thread that changing the wheel variant on the new T6.1 platform is a one-way street. i.e. you can increase the variant but not go backwards. So my approach was to increment the variant one step at a time, hoping they scaled in a relatively linear fashion.

Step 1 - set to variant 2. Coding was rejected (Request out of range).

View attachment 159453

Step 2 - set to variant 3. This time coding was accepted, and my IDE00845 values were increased to 2111mm / 2195mm respectively.

View attachment 159455

A quick test drive confirmed my speedo error was reduced to about 2-3 mph.

Step 4 - set to variant 4. Coding was rejected (Request out of range).

Step 5 - set to variant 5. Coding was rejected (Request out of range).

Step 6 - set to variant 6. Coding was accepted, and my IDE00845 values were increased to 2195mm / 2294 mm.

View attachment 159456

Another test drive and now my speedo is pretty much bang on. At this stage I was very happy to call it quits. Whilst I could have tweaked it higher so that the speedo reads a little higher than actual (as is common practise), I wasn't willing to risk a large leap in circumference knowing that I couldn't revert back. Incidentally I did try going backwards just to verify, and can confirm you get 'Coding Rejected Error 22' which prevents you from doing so.

Thanks to everyone who chipped in with advice, particularly 'AudiGit' on the Ross-Tech forums (where there's a similar thread to this) who gave me sufficient confidence to go for it!

I hope this helps out anyone looking to do a similar tweak.

Hiya Jimmy,

AudiGit would be me, you’re very welcome bud.

I have a T6.1 booked in with me where someone has fallen foul of the one way coding so it would seem that this is still an issue. Visited the van yesterday and confirmed it’s been coded to Variant 8 and is now erroring.

However, this will give me an opportunity to check the latest TPIs to see if VW have a solution for this, although I’m not hopeful. I wasn’t plugged into ODIS yesterday to be able to check.

Recommendation is to replace the cluster so I’ll be returning to install it later this week.

I’ll report back what I find, if anything.

 

[racerke600]

Hiya Jimmy,

AudiGit would be me, you’re very welcome bud.

I have a T6.1 booked in with me where someone has fallen foul of the one way coding so it would seem that this is still an issue. Visited the van yesterday and confirmed it’s been coded to Variant 8 and is now erroring.

However, this will give me an opportunity to check the latest TPIs to see if VW have a solution for this, although I’m not hopeful. I wasn’t plugged into ODIS yesterday to be able to check.

Recommendation is to replace the cluster so I’ll be returning to install it later this week.

I’ll report back what I find, if anything.

Hi Audigit,
You don't know me, but i've read your posts on the Rosstech forum.
I have a T6.1 and changed the coding with OBD11, I choose variant 8 to start with.
The problem that i couldn't revert back to a lower setting was 'quickly' confirmed, at the time i changed this, there was almost no one who did this before...
We tried everything with ODIS etc... but the only solution seems to be, a new cluster. Even a second hand one doesn't work.
And the new cluster has to be restored from the factory settings!
I'm still driving around with the variant 8 setting, and whenever i change to 5th gear the cruise control and start-stop won't work.
Somewhere somehow the circumference is used toghether with the gear and the speed to do a 'check'.
It seems that the car can tell that the revs/speed/wheel circ. don't match the selected gear etc...
It's givven me a headache and i can't believe VW doesn't know about this issue.

Greetings

 

[Lightrofit]

Hi Audigit,
You don't know me, but i've read your posts on the Rosstech forum.
I have a T6.1 and changed the coding with OBD11, I choose variant 8 to start with.
The problem that i couldn't revert back to a lower setting was 'quickly' confirmed, at the time i changed this, there was almost no one who did this before...
We tried everything with ODIS etc... but the only solution seems to be, a new cluster. Even a second hand one doesn't work.
And the new cluster has to be restored from the factory settings!
I'm still driving around with the variant 8 setting, and whenever i change to 5th gear the cruise control and start-stop won't work.
Somewhere somehow the circumference is used toghether with the gear and the speed to do a 'check'.
It seems that the car can tell that the revs/speed/wheel circ. don't match the selected gear etc...
It's givven me a headache and i can't believe VW doesn't know about this issue.

Greetings

Hiya Racerke600,

Yes it does seem that way. VW are aware of the issue but because it’s not likely to be an issue that’ll cause them financial loss or marketing backlash, they aren’t motivated to correct it.

With a retail cost of £1,200 inc vat, it’s a costly error to repair. I saw you mention previously that a used cluster wasn’t able to be matched to the van, what rejection was it? Immo issues?

I haven’t checked recently but it could be worth seeing if there are any files from VCP that may help.

If anyone has this and replaces their clocks, the old ones may be useful in testing on the bench to see if they can be repaired off the vehicle.

In fact, I may be able to keep the old clocks from the van I’ll be repairing this week, the clocks are useless to anyone else. I’ll ask them nicely lol.

 

[Lightrofit]

So I revisited the offending vehicle today and completed a successful cluster replacement.

If this had been at a dealership then their procedure would have seen the coding copied over, nuking the new cluster.

So at least I can confirm that there is a way to get a new cluster installed and working.



Hopefully that will help someone. Albeit ODIS is needed for the swap so you may need to seek support from a local independent specialist.