Thread: Nüvi 3790

Originally Posted by Choco

Today I took a trip with the route programmed in the nüvi and there was a moment when it turned off and restarted by itself. The curious thing is that it has continued with the planned route it had.

Can this also happen again if I convert it to a 34xx?

Quite possibly it will continue because it's confirmed that your device's rgn41 can't be erased despite the 'success' report in update.log file. That failure to erase is either (i) because it contains severely corrupted irremovable data; or (ii) perhaps it has some physical flash damage which is affecting only or mostly where 41 is located.

Neil, it is true that we cannot do a complete erase of region 41, the tests carried out confirm it, can we do a format of that region? For example, in Ms-dos, a command (del), (deltree) or (format) is not the same as having different operations and results as far as write elimination is concerned.

Whichever reason it happens to be, (i) or (ii), is academic anyway because erasure of a region in Garmin is as close as we get to a formatting. Not quite like it, but approaching a Windows re-format of an individual partition on a drive as an approximate analogy. There's an exception to that of course, that is the one region where the file system is stored. If you were to erase region 48 (using ergn,48), because it's formatted in FAT32 and made to mimic a Windows partition or drive, it will show in Disk Management as unallocated (just like when a volume has been deleted in Windows) and so have to be properly formatted again as FAT32... but cure fw would need to be loaded to have Mass Storage Mode enabled after 48 is erased i recall. All other physical regions, including 41 which is additionally encrypted in simple XOR, cannot be truly re-formatted by any method in my experience. Some can't even be erased because they're protected. Some are not physical - region 12 for example is virtual. Butters made some further explanations in [Only registered and activated users can see links. ]

Neil, would it be possible to transform to 34xx in terms of recovering voice commands, bluethoo, DEM maps, 3D maps, real view (JVC) but with the satellite controller (GPS) (PCB controller?) of the model 37xx? I mention this, because if the 37xx model's radar controllers could be used, we would possibly avoid the car's jumps and the inaccuracy of the GPS.

I guess you mean by exchanging the GPS firmware components. That's way beyond my capabilities i'm sorry. I recall there was discussion in one of the 37>34xx threads years ago when we had many talented programmers posting here who had vast experience with and understanding of ARM-type processors and Garmin's OS and firmware adaptations. But even with those clever guys looking into it, unfortunately it came to nothing.

We've both put a lot of time and effort into trying to restore your 3790. I'm probably almost as disappointed as you are that we haven't been able to fix it mate. Sorry.

Originally Posted by Neil

We've both put a lot of time and effort into trying to restore your 3790. I'm probably almost as disappointed as you are that we haven't been able to fix it mate. Sorry.

First of all, thank you very much for all the attention and help that Neil has given me. This whole adventure will remain in my memory forever, because the nüvi has a very important sentimental weight for me, and all of this is already part of the history.



I'm thinking the following:
- The nüvi, like 37xx, is practically very basic, it does not have voice commands, it does not have Bluetooth, it does not have JVC, it does not have 3D maps, it does not have DEM maps, in short, only the basic function and good GPS accuracy.
- I'm thinking, if I could transform the nüvi into 37xx Sg/My:
Will I have 3D maps activated?
Will I have DEM maps activated?
Will I have True View Assist (JVC) enabled?
Will I have good GPS accuracy?

I tell you this, because losing voice commands and Bluetooth wouldn't matter to me, that is, if in exchange I get the rest of the things I mentioned.

A hug.

You can see what features an SG/MY 3790 supports and other specifications in the links below:

Code:

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I think it'll probably be fine for accuracy if there's a PCB P/N match so first ensure that the SG/MY fw has as one of the PCN P/Ns written in it which matches that of your device's board version - read this thread to learn how to find PCB P/Ns (105-xxxxx-xx), both on the device itself and in the intended firmware: [Only registered and activated users can see links. ]. If there's a match you can safely try a hybrid fw (US/EU boot.bin and the remainder of SG/MY fw, retaining HWID as 1101). Using original boot.bin and HWID makes a re-conversion more likely, not 100% guaranteed although it's usually very safe. If you satisfactorily test hybrid fw, a full conversion to SG/MY with HWID 1288 should then be totally safe. Be aware because your device can't seem to even effectively clear nonvol that even more problematic data might build up by cross-flashing to Asian, although i'm thinking that because the device itself can't now write to region 41 further potentially bad data won't accumulate. It might even turn out that the device might now not be capable of being flashed effectively in other ways either. Damaged/corrupt nonvol that can't be cleared or erased will nearly always cause serious problems eventually.

Note that before you try a conversion to SG/MY you should first remove all EU/US specific files from the device - VPM voice files in particular can cause problems. That's because incompatible files may cause it to 'soft-brick' instead of booting - by freezing on the splash screen, spontaneously shutting down or bootlooping. Be aware that some Asian devices or fw conversions have problems when Western voice files are used, so SG/MY might not support Spanish at all. You can adjust for that perhaps by adding it using turboCCC's RGN Voice Editor, info here in this post #63: [Only registered and activated users can see links. ], and read the start of that thread too for other methods. Also some tips here might help you too: [Only registered and activated users can see links. ].

Originally Posted by Neil

You can see what features an SG/MY 3790 supports and other specifications in the links below:

Code:

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Hello Neil, thank you very much for providing me with all this information, I would be unable to get to it without your help.
The 3790 Sg/My and the 3790 EU/UU look practically the same device. The most important thing for me would be that the 3D maps, DEM, and precision worked well, since now like 37xx I don't have anything activated.

Originally Posted by Neil

I think it'll probably be fine for accuracy if there's a PCB P/N match so first ensure that the SG/MY fw has as one of the PCN P/Ns written in it which matches that of your device's board version - read this thread to learn how to find PCB P/Ns (105-xxxxx-xx), both on the device itself and in the intended firmware: [Only registered and activated users can see links. ]. If there's a match you can safely try a hybrid fw (US/EU boot.bin and the remainder of SG/MY fw, retaining HWID as 1101). Using original boot.bin and HWID makes a re-conversion more likely, not 100% guaranteed although it's usually very safe. If you satisfactorily test hybrid fw, a full conversion to SG/MY with HWID 1288 should then be totally safe.

Neil, I can't show the PCB P/N table in the hidden content, I don't know why. Can you provide me with the list?
When I can read the list, if my PCB P/N supports the conversion to SG/My, before doing it, I will show the hybrid firmware-software to make sure I have done it right. Converting the nüvi 37xx to 3790 Sg/My could be a solution. I mention it, because converted as a nüvi 34xx, everything works well, except the voice commands and the precision of the GPS, in addition, I love the user interface, it is fast and very intuitive.

Originally Posted by Neil

Be aware because your device can't seem to even effectively clear nonvol that even more problematic data might build up by cross-flashing to Asian, although i'm thinking that because the device itself can't now write to region 41 further potentially bad data won't accumulate. It might even turn out that the device might now not be capable of being flashed effectively in other ways either. Damaged/corrupt nonvol that can't be cleared or erased will nearly always cause serious problems eventually.

[/QUOTE]


Here's the bad thing, but this is very curious:

The conversion to 34xx is done correctly, although it is true that as 34xx I still have things to try, for example: JVC.
When I delete nonvol as 34xx, the favorite places are not deleted, it behaves the same as 37xx, anyway, here we have something damaged that does not allow us to delete it correctly.
In the favorite places the place of Garmin Asia, Garmin UU and Garmin EU is also saved, when I delete them from saved places, I can delete everything, but when I do it from nonvol, everything I delete reappears. I mention this, because Could it be that the favorite places are saved in the same storage as the Garmin places and that is why when you delete the nonvol and restart they appear again?

Although I have the feeling that if at 34xx the system works well, it could be that at 3790 Sg/My it would work well.

Originally Posted by Neil

Note that before you try a conversion to SG/MY you should first remove all EU/US specific files from the device - VPM voice files in particular can cause problems. That's because incompatible files may cause it to 'soft-brick' instead of booting - by freezing on the splash screen, spontaneously shutting down or bootlooping. Be aware that some Asian devices or fw conversions have problems when Western voice files are used, so SG/MY might not support Spanish at all. You can adjust for that perhaps by adding it using turboCCC's RGN Voice Editor, info here in this post #63: [Only registered and activated users can see links. ], and read the start of that thread too for other methods. Also some tips here might help you too: [Only registered and activated users can see links. ].

Interesting about the voice editor.
Yesterday I converted the nüvi 37xx to 34xx again, I will try the tool to see if it solves the problem of voice incompatibility of voice commands and to see if it works for the 34xx.

One question Neil: If my nüvi had a compatible PCB P/N to transform it into a 3790 SG/My, would it become a 3790 SG/My or a 37xx SG/My?

A hug!

Originally Posted by Choco

........ The 3790 Sg/My and the 3790 EU/UU look practically the same device. ........

Externally at least they seem very similar. The SG/MY does additionally have an external socket for headphones i think.

Neil, I can't show the PCB P/N table in the hidden content, I don't know why. Can you provide me with the list?

Are you looking in the correct "hidden content"? Hold the battery symbol on the main 'Where To?/View Map' page for about 5 or 6 seconds to reach a hidden menu headed 'SW Ver .....' then press 'Next'. Then you'll see your device's PCB P/N listed at the top of next page headed 'Version Information ....'. This is an example below only, yours might differ slightly depending on board version but should include 01652:
[Only registered and activated users can see links. ]
The possible PCB P/Ns for SG/MY 37xx series should be found in its firmware. When examining the fw as an RGN file in hex reader you are looking to find the string 31 00 30 00 35 00 2D 00 30 00 31 00 36 00 35 00 32 (e.g. search for 1.0.5.-.0.1.6.5.2. in text, where "." is wildcard/joker 2E character), if there's no match the conversion might fail.

When I can read the list, if my PCB P/N supports the conversion to SG/My, before doing it, I will show the hybrid firmware-software to make sure I have done it right. Converting the nüvi 37xx to 3790 Sg/My could be a solution. I mention it, because converted as a nüvi 34xx, everything works well, except the voice commands and the precision of the GPS, in addition, I love the user interface, it is fast and very intuitive.

It may be only that you lost ASR in 34xx because Voice Command in 34xx uses ASR2 and 37xx uses ASR1 .... so like flashing a new logo after conversion the ASR etc. files need to be changed too. i can't recall because it's so long since i messed with that conversion so do some checking in the relevant threads.

........
When I delete nonvol as 34xx, the favorite places are not deleted, it behaves the same as 37xx, anyway, here we have something damaged that does not allow us to delete it correctly.

Yes, hence my concern that the more cross-flashing done the more likely potentially 'poisoned' data could be accessed in rgn41 which will result in a bricking. It's never certain to what degree the device itself can access and use 41 in a case such as yours. It may be that it's completely "locked-out" of 41, in that not only can't it write new data it can't even read existing data there.... but i don't know for sure but i suspect it's the latter.

In the favorite places the place of Garmin Asia, Garmin UU and Garmin EU is also saved, when I delete them from saved places, I can delete everything, but when I do it from nonvol, everything I delete reappears. I mention this, because Could it be that the favorite places are saved in the same storage as the Garmin places and that is why when you delete the nonvol and restart they appear again?

I don't think that should be unexpected. I suspect those so-called "POIs" for Garmin offices aren't saved like 'favourites' that you create yourself which are retained in the nonvol memory which is normally clearable from a healthy device via Clear User Data or Clear NV.

Interesting about the voice editor.
Yesterday I converted the nüvi 37xx to 34xx again, I will try the tool to see if it solves the problem of voice incompatibility of voice commands and to see if it works for the 34xx.

RGN Voice Editor is to enable incompatible VPM voice files to be used in devices where they're not originally enabled in firmware. Your problem of Voice Command not working in 34xx is more likely to be due to ASR file differences as i mentioned above.

One question Neil: If my nüvi had a compatible PCB P/N to transform it into a 3790 SG/My, would it become a 3790 SG/My or a 37xx SG/My?

Only one way to find out really which is to try the conversion, i think it's likely an each-way bet that it'll have full SG/MY functions.

It's a good chance that if there's physical flash damage causing 41 to be acting like it is, and that the damage will spread to other parts of the flash memory so eventually the device will become unusable - just like you see when any flash drive or SSD fails slowly. If the problem is instead because there is so much badly corrupt data in there but the device still can read it then eventually it might randomly access some few bytes that kill it completely. Just be prepared for the possibility that you might be spending all this time recovering it only for it to suddenly die unexpectedly. I hope it doesn't seeing you're so dedicated to getting it running properly again.

Hello Neil, you are a crack! If it weren't for all your support, I wouldn't have gotten this far in life.
I have been looking at the P/N PCB of my nüvi and searching in the sequence. I've been lucky that my PCB P/N is identical to the one in the photo you gave me, because I don't know how 105-016xxxxxx is converted into that sequence of numbers. I attach some images of what I found in file 3790_SG/My.rgn. I understand that there is a coincidence and the transformation could be attempted.

Spoiler: [url=https://postimages.org/

[/url][Only registered and activated users can see links. ]

Originally Posted by Neil

It may be only that you lost ASR in 34xx because Voice Command in 34xx uses ASR2 and 37xx uses ASR1 .... so like flashing a new logo after conversion the ASR etc. files need to be changed too. i can't recall because it's so long since i messed with that conversion so do some checking in the relevant threads.

I have been reading about it, if I'm not mistaken, Catymag refers to the beginning of the thread and leaves the files in post 36 and 37. I think they are these if I'm not mistaken, but I can't download them.

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I don't know how voice commands work. He thought that the files the application used depended on the map that was installed along with the ASR folder. Just like the actual view with your JVC folder. He thought that if it did not work or there was a problem with the voice commands (as long as the icon appears in the utilities menu) it was because the installed map did not have the corresponding files to work properly.

I will take a trip shortly and I will be able to check if the JVC works well as a 34xx. I am convincing myself that perhaps it is the best option to leave the nüvi as 34xx. Although I don't rule out trying to transform SG/My as you told me.

Originally Posted by Neil

Yes, hence my concern that the more cross-flashing done the more likely potentially 'poisoned' data could be accessed in rgn41 which will result in a bricking. It's never certain to what degree the device itself can access and use 41 in a case such as yours. It may be that it's completely "locked-out" of 41, in that not only can't it write new data it can't even read existing data there.... but i don't know for sure but i suspect it's the latter.

Let's hope not, but if it happens, it is something that we will not be able to avoid.

Originally Posted by Neil

I don't think that should be unexpected. I suspect those so-called "POIs" for Garmin offices aren't saved like 'favourites' that you create yourself which are retained in the nonvol memory which is normally clearable from a healthy device via Clear User Data or Clear NV.

Ok.

Originally Posted by Neil

RGN Voice Editor is to enable incompatible VPM voice files to be used in devices where they're not originally enabled in firmware. Your problem of Voice Command not working in 34xx is more likely to be due to ASR file differences as i mentioned above.
Only one way to find out really which is to try the conversion, i think it's likely an each-way bet that it'll have full SG/MY functions.

Perfect, now I understand it better! This tool is only for Asian firmware-software. I'll probably have to use it if I convert to 3790 SG/My and the voice commands don't work. Thanks Neil! Sometimes you read so much that it is difficult to organize things well.

Originally Posted by Neil

It's a good chance that if there's physical flash damage causing 41 to be acting like it is, and that the damage will spread to other parts of the flash memory so eventually the device will become unusable - just like you see when any flash drive or SSD fails slowly. If the problem is instead because there is so much badly corrupt data in there but the device still can read it then eventually it might randomly access some few bytes that kill it completely. Just be prepared for the possibility that you might be spending all this time recovering it only for it to suddenly die unexpectedly. I hope it doesn't seeing you're so dedicated to getting it running properly again.

Thank you very much for everything Neil, from the bottom of my heart, if your clarifications were going crazy.
All my efforts to make my nüvi work as well as possible is because it annoys me, a lot, that due to a damn update, my nüvi cannot even display 3D and DEM maps, not to mention other features that it has lost.
Little by little, I'm getting the idea that it could be that with all this effort to improve the nüvi, I screw it up and it becomes useless.
The truth is that nowadays, there are navigators integrated into vehicles, the nüvi is almost not worth using, but I love it so much that I can't see it malfunction, so if it dies trying, it will hurt me. , but I'll accept it.

A hug, thank you very much.[SPOILER][/SPOILER]

Regarding US/EU 3790>SG/MY 3790:
Yes it should be able to successfully convert to SG/MY because of the matching PCB P/Ns, however you'll then still need to be able to source (or maybe adapt) some required files for it, voices for example. Many files will be SG/MY specific and might not be so easy to find there days. Incompatible US/EU specific files onboard will just soft-brick it on first power up, most likely that's why it wouldn't boot on your last conversion attempt.

Regarding 3790>3490:
Many of the *.ASR and ASR-related voice control files are indeed map-dependent however some are not. i.e. Some will need updating with the map but others stay the same.

If your device has Lifetime Map entitlement of NTU Europe it'll be easier after conversion because GarminExpress will continue to supply map updates based on it's Unit ID along with appropriate associated files based on its HWID (if available). If it's an earlier 3970, even if it's LM, it may have been originally factory programmed with NT (non-unicode) EU maps and unfortunately many of the associated files meant for 3490 (NTU use) are not suitable for the NT maps (because 3490 was only ever supplied with NTU). Many early 37xx didn't have an LM entitlement either, only a "One-Off" update was guaranteed. I think yours might be a later issue because of it's 8GB flash size and higher UID, so it's likely not just LM but using NTU maps anyway.

So in short, if your 3790 already uses LM NTU it will be far less problematic to get correct files after conversion to 3490 than if it has an earlier NT entitlement - whether that's LM or One-Off in NT.

Although some 'old hands' reading this thread might scoff at your efforts to revive your crippled device and my attempts to help you thru it, i can fully understand your attachment to it and the 'emotion-based' desire to keep it running. I've got more ancient Garmin devices, some well over 20 years old in fact, which i keep going for the same reason even though their monetary value is a mere few dollars nowadays. Please press on and good luck.

As far as i'm aware there's no specific thread but you can search generally for "Convert 3790 US/EU to SG/MY", maybe there's something from years back. I seriously don't recommend that conversion unless you have a deep understanding of the various files specific for both devices. Otherwise, the safest way is to do a hybrid-conversion after removing all region-specific files then painstakingly gradually add files back individually and power it on each time to see if it soft-bricks.

As for a 3490 conversion, with the correct Voice Command related files (ASR2 only) and a full NTU EU map the voice command function should work. The map (NT or NTU) you have on-board can be checked via "My Maps" in settings; or connecting to a computer and looking at the content of GarminDevice.xml file found in the Garmin folder.

Unfortunately Garmin device regions cannot be accessed by a computer in that way, other than of course the file system region (either 48 or 83) which has format of FAT32 and is therefore visible, writable etc. and can additionally be formatted and checked by ALL the usual tools just like any other USB flash drive can be treated, including using CHKDISK etc.. All other populated regions are effectively invisible to a computer.

The only way to 'see' the content of region 41 is to firstly decrypt a dumped BIN file copy of it (unlike other regions, nonvol is encrypted). We then can look at it's data in a hex editor. There's little practical value in doing that usually anyway - if you did know what data to remove, replace or add, then after making changes you re-encrypt it's data and manage to flash it back it to a healthy device the nonvol just gets updated/rewritten again on the next boot-cycle. I don't think your faulty device can even access rgn41 regardless, because it can't be erased using "ergn,41" text command. - that's essentially why it can't be restored as US/EU 3790.