How to make a service (cure) firmware for your Garmin unit

**catymag** · 30th March 2011, 04:43 PM

How to make a service (cure) firmware for your Garmin unit

As said here:
[Only registered and activated users can see links. ]
you can get a software missing message ,after a firmware update, or if your unit boots and reboots after loading a map ,a track ,a poi or something similar, you'll need a service software to cure your Garmin gps and see it booting normally again.

To create and load it ,you will need 4 things:

1)Your unit firmware (use a previous one not the one you have on your unit)
You can get it directly on Garmin server (now many have been deleted) , on Perry site

Code:

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look also here :
[Only registered and activated users can see links. ]

2) Turboccc RGN_Tool
here:
[Only registered and activated users can see links. ]
3) an Hex editor
here

Code:

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4) Updater.exe
here
[Only registered and activated users can see links. ]

First open RGN_Tool and drag in it your downloaded GUPDATE.GCD.
In my case is FW 2.50 for 3790.

Now save the file in the following way (example for 3790-firmware 2.50):
The first four digits must be 1101 (the hardware ID) followed by 01000 , followed by the firmware number 250.
It will be :110101000250.rgn : 3790 original 2.50 FW.rgn
Yours will be xxxx01000xxx.rgn

Now open HxD and drag the .rgn file in it.
We have to change some values related to some extensions (.img .GCD .gpx .gpi .zip .vpm)
Why ? Coz one of these files prevents our nuvi to boot normally , changing the extension the firmware wont find the corrupted one anymore and will boot.
So let's change them.
click on Search and then Find and fill the opened window like that

Then click ok.

the editor will find the .img extension, let's change them all.
Select the i and replace it with x and clicking F3 find and change all the .img extensions to .xmg

We'll do the same with all the .GCD .gpx .gpi .zip .vpm extensions

Must be sure to change them all!

Now save the new cure file as 110101000250_cure.rgn (example for 3790 fw 2.50). Yours will be xxxx01000xxx_cure.rgn

Now load it in your unit , after having attached your device usb at your pc, in preboot mode:

Code:

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tick USB mode ,drag&drop the .rgn in updater icon, flash your gps.

After flashing it , your device should boot and you can delete the corrupt files who caused the problem.
Reflash now it again with the original.rgn and then you ll be able to update your device to the latest firmware using webupdater.
Edit : or now use this great tool by Kunix
[Only registered and activated users can see links. ]

**ddabcd277** · 31st March 2011, 06:59 AM

Nice. But not always helpful. Sometimes there could be bad sectors in the memory or sometimes nuvi just not want to boot even if you change extension of the files gpi, gpx, img, vpm, jpg, srd,srx, asr, srf, gcd etc. IMHO the best way is changing the drive letters everywhere in the memory. Here how to make it in Hex:

Find and Replace everywhere in the .rgn (boot+fw_main):
30 00 3A 00 2F to 00 00 3A 00 2F
31 00 3A 00 2F to 00 00 3A 00 2F
30 3A 2F to 00 3A 2F
31 3A 2F to 00 3A 2F

Here is such an example:

Code:

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I have wrote it here also:
[Only registered and activated users can see links. ]

Hope it is helpful.

Cheers,

**Tzidogang** · 1st April 2011, 04:17 PM

If the problem is from the Keyboard. Can we just change the .kbd into .xbd without changing other file extension?

**Evgeny Kosourov** · 26th April 2011, 08:12 PM

Thank you very much for this instruction. Today, the reformed its 3790.

**Tesla280684** · 18th May 2011, 07:27 PM

It works for my 3760t. thx a lot!

Greetings from Argentina

**VMatas** · 21st May 2011, 06:07 AM

During map update process map update tool hangs, and after kill process from task manager restarted Nuvi 3790 goes into loop "Loading Maps"

After long game with cure firmware i found, that if i change 30 00 3A 00 2F to 00 00 3A 00 2F device enters in to PC connection mode. Unfortunately, computer doesn't recognize it as Mass Storage device

Anyone, any suggestions what i need to do now?

**ddabcd277** · 21st May 2011, 08:01 AM

@ VMatas

Didn't quite understand the comment. If your nuvi has entered in PC connection mode (you can see the PC icon on the screen) then it should be recognized as a Mass Storage Device. Try reinstalling the Garmin USB drivers:
[Only registered and activated users can see links. ]

Here is a cure firmware 4.10 I prepare for 37xx series. Hope it is helpful:
[Only registered and activated users can see links. ]

Normal FW 4.10:
[Only registered and activated users can see links. ]

**VMatas** · 21st May 2011, 12:22 PM

Yep, i also not understand why my PC and laptop can't see nuvi... strange. Anyway thanks, i will try your suggestions.

**VMatas** · 21st May 2011, 02:05 PM

No way.. drivers updated. Windows XP and Vista doesn't see it, MAC OS X too, using my cure firmware and yours - no changes.. Nuvi shows PC connection icon, but it can't be recognized. Don't have any idea why. May i need contact Garmin support on Monday?

**ddabcd277** · 21st May 2011, 03:48 PM

Sorry, don't have any more idea haven't seen such a problem before. If you have a different USB cable you can try with it. This is the only thing I can think of. Maybe the problem is coming from the USB cable. Don't know. Wondering what would Garmin support says. Hope you fix it.

Cheers,