Hi gaga24,

I still do not have the answer, but could you please check the vin number on the ttgo.bif generated by the carminat ?
howto :
- download explore2fs-1.08beta9.exe (free, no install)
- open the ext3_loopback file in the loopdir directory (kind of "dump" of the internal memory)
- view the ttgo.bif file on the root directory

-> check the VehicleIdentification=VFxxxxxxxxxxxx

and see if it corresponds to your vehicule (registration document) or to the faulty scenic. In my case, the number does not match (matching the vehicule of the wrong card) so I suspect the mismatch VIN number to cause the "no comm" pb between the main multimedia unit and nav unit.

That is actually quite a good find, did you correct the number and did it change / fix the problem?
Although it wouldn't surprise me if this Vin number is nothing like bogus with no effect at all.
In any case you would expect the TT to actually check the number and for a fresh install install to read out the current one instead of just taking over the number from a different SD.

I had a backup of the "original" loopback file with the correct VIN that I put into the card, but it was overwritten by the Carminat with a new loopback that contains the wrong VIN. If the internal memory has been updated once when I put the wrong card, there must be a way to update it again

Yes im sure VIN is changed.
From original file it was VehicleIdentification=VF****************656 and now is VehicleIdentification=VF*************986 same as VIN from other car. Now i have two Scenic with same VIN number. Luckily i was save the info in notepad before update.
What to do, any suggestion? If i change VIN number in loopback.ex3 file, will nav accept this?

Ok, I'll try to sum it up:
We agree that on all cars with broken remote the Vin number has changed - for whatever reason.
We also agree that an update or backup did not help.
Correct so far?
The Vin number is stored in the loopback file, which usually stays inside the Carminat but the file is written on a new SD as part of the initialisation.
The Vin number is also located in the ttgo.bif file.
The interesting bit to know would be if in either file the Vin number is still correct.
If not it would mean the Carminat basically got transfered to a new vehicle. (Which is total crap is that is the case!)
For the Carminat to accept any updates the said update must be newer than the installed system, but I did hear that users were able to downgrade the system using an older version of the Navcore.
What needs to be tested:
Changing the Vin in the loopback and ttgo.bif file on a SD - while doing so delete all user related files like mapsettings.cfg, currentmap.dat and so on, this should force the Carminat to re-initialise the SD and hopefully take the data from it as well.
If that is of good I would suggest to try a downgrade to the previous Navcore but with a loopback file that contains the correct vin number.
Last but not least would be to call TT and state that your dealer used a different SD for an update, that this has changed the vin number on the Carminat and that the remote no longer works - ask for specific instructions on how to get the Carminat linked to YOUR car and remote again.

Yes, correct. Nothing else to do but to try. I will do it next week. Is it possible do downgrade 8842 to 8841?

I can't answer that correctly as I never tried
Having no access to a Carminat makes testing a bit hard.
But if I recall correctly TT offers a "rescue system" for bricked devices, maybe start from there?
Just check the TT support for the download.

I'm going to verify vin in ttgo.bif and if it's not the same(clio III), I'm going to modify vin in ttgo.bif in loopback.ex3 this week end.

Keep us posted about the progress!

Is there any way to write on ext3 partition on Windows ? Ext2IFS and Ext2fsd only mounts physical partitions, and explore2fs is read only...

[Edit] Using filedisk-17 does not work for me (Windows 8.1), even using the filedisk-15 (signed one), it says "cannot find the specified path", even with administrator privileges...

I am not 100% sure but I think I used the Deamon tools for it last time I tried.
Although the best way would be from within Linux, a good Live CD should do.

I will use virtual machine and Linux. This stuff filedisk-17 with windows 8 dont work.

I managed to recreate the file " loopback.ex3 " but the GPS automatically replaces the " ttgo.bif " file that I modified . I used WinImage to open the file " loopback.ex3 " and I extract the contents . I created a ext3 partition 16MB in SD with the software " MiniTool partition wizard " . I installed the driver " ext2fsd " Then I copy the file to the ext3 partition. Then I used the software " USB Image tool" to recreate the " loopback.ex3 " file.

Ok, as a lst attempt:
Download this [Please Register or Login to download file] , unpack and copy the extracted content to the root of your SD card.
If you use your orginal make a backup first.
If there is a ttsystem.ib present delete it before proceeding.
Insert the SD into your Carminat and switch on, check if the remote works again.

Problem is that the bootloader prevents loading anthing that is not a TT install file, the content on the SD are a copy from the Carminat internal system
This cycle needs to be broken in order to replace the faulty Vin in the internal system.
The above Zip is the only thing I could find that should install in all cases but I don't know if it "resets" the whole system to the correct defaults.
I suggest to try first with an empty SD in the hope that it will erase the interam memory, if no luck try with all your files on the SD but an edited ttgo.bif containing the correct vin number.

Sorry to hear this. I will try to downgrade to 8841 and then put the SD card with corrected VIN but with 8842 navcore.
Hope this will make system update same as before. Keep us posted.