GPSMAP 66 is Non-Functional After firmware 4.70 Update

[sammyB]

I tried to download to 4.20 but this didn't work either
I had also an expert looking into it,and he says that de file GarminDevice.xml is missing

Sammy - Is your unit bricked also? If so how did someone determine the xml file is missing. On mine that would be impossible as there is no way to access the device. Did you load any geocaches after updating to 4.7?

I used JaVaWa device manager,under extra you can see report and check for updates. works great.

[sammyB]

I also used this program 'RGN Firmware Install' ,it works fine everything is working again.

[CheminerWill]

So what's the conclusion? Not to install 4.7 when having large ggz?

I also used this program 'RGN Firmware Install' ,it works fine everything is working again.

I have continued to have problems even without a ggz file. At first it seemed only to crash when my 32GB SD card was inserted. But then I had a boot freeze without the card installed. It is possible though that on that one boot, I had not deleted the SQL folder so that may be why it crashed even without the card in.

In any case, today I will be downgrading to 4.2 for now and if asked my cautious opinion would be wait until Garmin fixes this before installing 4.7. I really wanted to try out the new proximity feature, but that will have to wait.

GPSrChive told me that I did not have to use the RGN Firmware Install to do the downgrade. You can just get the 4.2 firmware from the link in the "GPSMAP 66 Firmware Update History" box on the GPSrChive firmware page. Then follow the installation for "GCD Update Procedure" on the same page. And at this point, I would trust anything GPSrChive tells me way more that what I might hear from the Garmin telephone support system!

[UglyTim]

GPSrChive told me that I did not have to use the RGN Firmware Install to do the downgrade. You can just get the 4.2 firmware from the link in the "GPSMAP 66 Firmware Update History" box on the GPSrChive firmware page. Then follow the installation for "GCD Update Procedure" on the same page. And at this point, I would trust anything GPSrChive tells me way more that what I might hear from the Garmin telephone support system!

That was what I tried first after I got into the device using forced USB mode. Deleted .ggz file and put gupdate.gcd for 4.20 on it. Device was still hanging up upon boot and did not install the firmware. RGN firmware install seemed to be the only way to fix the device in my case.

[GPSrChive]

You needed to delete the Garmin/SQL/ directory to prevent the lockup after power on.

[CheminerWill]

Just a FYI update. I went back to 4.2. I did need to redo some of my settings after the downgrade. I then installed the SD card and loaded two .ggz from GSAK to the card. All is working fine so far.