Transform a Nuvi 37xx in a Nuvi 34xx for dummies

**Neil** · 17th June 2015, 02:36 AM

Yes. Both GE & WU will offer new software as it's available, as if the device was 'natively' 34x0 as i said.

**kevindd992002** · 17th June 2015, 04:10 AM

Ok, thanks.

And by the way, with firmware v8.20 it seems that the 3790T unit is as accurate as it is before conversion. Did they include a driver for the old GPS module already?

And one more thing, I'm experiencing a discrepancy between the speedometer reading on the garmin unit and the speedometer on my car. They differ at about 8kmh, the speedometer of the car being faster. Is this because of the wheel configuration of my car? Does that mean the GPS reading is more accurate?

**Neil** · 17th June 2015, 07:14 AM

Check the accuracy in the sat page [hold the bars on top LH corner on the main screen to access it]. Many ppl complain the they had 3m accuracy routinely before conversion but not afterwards. See this thread: [Only registered and activated users can see links. ]. It seems to depend on the gps chip fitted, one is just more compatible with 34x0 software than the other apparently.

The GPS's speed reading is certainly quite accurate provided the sat fix is good. Speedos in cars seem to read up to 10% over in many countries. It varies though, my late model Subaru Liberty reads about 8% over, yet my 1992 L series wagon reads smack-on. Go figure. Cars i've hired in the States all seem to read accurately, same as a GPS anyway. Id trust the GPS reading before the car speedo once it's got a stable fix.

**kevindd992002** · 17th June 2015, 12:51 PM

I could've sworn that the reason, in the past, why I went back to the 3790 original firmware (after converting my device to 34xx) is that it was way too inaccurate when using the 34xx firmware.

That's what I thought. I already tried it in two cars and it seems to exhibit the same behavior. I guess it's just the standard speedo config in our country.

NOTE: I just read that thread you've posted and it seems that the OP says that he was also having the same inaccuracy problem AFTER changing to the 34xx firmware for his 3760 device.

**sandra22** · 30th June 2015, 08:07 AM

Hello,

A few days ago my 3760 converted it in 3490 and it happened. Today I tried to return the device back to 3760, but during the update updater.exe spent a mistake and now the device does not start. The screen lights up, but nothing is displayed. Unable to enter the preboot mode.
Someone had any similar problem?

Problem solved - [Only registered and activated users can see links. ]

**catymag** · 30th June 2015, 09:32 AM

1)Backup region 41 before doing modding in nuvi!
2) use sd files to convert and to roll back.

sent with my phone

**sonataGL** · 11th January 2016, 12:18 AM

Hello Senior members,
Long ago I followed the instruction of these pages and transform my nuvi 3750 to 34XX. Recently for some reasons the device keeps on turning itself Off/On during navigation. To solve the problem it appears that I need to do a software update and a master reset on the device. I did the software update but wondering will the master reset brings me back to the 3750 ?
Will backing up region 41 and restoring help?
In advance thank you for any advice
Camissa

**Neil** · 11th January 2016, 01:22 AM

G'day Camissa. You should always have a backup of rgn41 kept permanently. Regardless, backing it up now and then immediately restoring it would only write it back byte for byte including any corruption if it was present. Do the backup now anyway, but it will be region 41 as 34xx device not 37xx.

A 'master' or hard reset will not return it to 3750, only reflashing 37xx firmware will do that. A reset [or clear nonvol] will delete all your user data however, so if you wish to save your favourites back up your GPX folder to restore after the reset. Doing a'clear nonvol' gives a little more comprehensive reset and just as easy to do as a hard reset. [Only registered and activated users can see links. ].

**sonataGL** · 11th January 2016, 02:06 AM

Thanks Neil, I do appreciate your prompt reply. I just did the backup of rgn41 and current.gpx and then cleared the nv. I have restored the current.gpx ( via temp.gpx). I will see tomorrow if this helps with the device turning off/on during navigation.
Update: run my old gps today for about 2hours and working fine.
Once again thank you for all
Camissa