Recovery
Forced USB Mass Storage Mode
- If your GPSMAP 66s/st is freezing or crashing during startup, it is commonly a recently added map, image, gpx or other file that is creating the issue.
- This procedure forces your GPSMAP 66s/st into USB Mass Storage Mode so that you can delete/remove/rename any recently added files:
-
Power the
GPSMAP 66s/st off (press and hold power button ~10 seconds to force power down
if necessary)
- Remove the batteries from your GPSMAP
66s/st
-
Connect the
GPSMAP 66s/st to your computer with a USB cable
-
immediately press and hold the D-PAD (Up) button
-
If
necessary, cycle the
(Power) button to initiate a power on sequence
-
Release
the D-PAD (Up) button after the USB symbol is displayed on the screen
- The
GPSMAP 66s/st will enter Forced USB
Mass Storage Mode
- Remove or rename any recently added maps, images, gpx or other files that may be causing the issue
- Disconnect the
GPSMAP 66s/st from the USB cable
- Install previously removed batteries
- Power the GPSMAP
66s/st
on
-
Repeat Steps 1-11 as needed until the
GPSMAP 66s/st boots properly
Forced RGN Firmware Installation
- This procedure (Windows only at this time) will force a low level installation of the GPSMAP
66s/st firmware
- After completing this procedure the GPSMAP
66s/st will be running the firmware version provided by the RGN file
- Warning: Flashing firmware to a device
other than that for which it is designed will render the device
permanently inoperable
Preparation
- Create a new empty
directory on your computer desktop and name it
'RGN'
-
Download
RGN_Tool.exe
to the
\RGN\
directory you created
- Download
Updater.exe
to
the \RGN\
directory you created
Extract
RGN from
GCD
- Download the desired
GCD file from the
Firmware
page to
the \RGN\
directory you created
- Extract the GCD file from the
downloaded .zip file
-
Delete the downloaded .zip file
- Rename the
GCD file to
gupdate.gcd
- Drag the
gupdate.gcd
file to RGN_Tool.exe
- Verify the HWID displayed in the RGN_Tool
window matches your GPSr HWID
- GPSMAP 66s, 66st HWID = 3028
- In the RGN_Tool window, select
'File > Save to RGN' and save as
gupdate.rgn
in the \RGN\
directory you created
- Delete the
gupdate.gcd file
from
the
\RGN\
directory you created
-
Close the RGN_Tool
Verify Progress
- The
\RGN\
directory should now contain these files:
-
RGN_Tool.exe
-
Updater.exe
-
gupdate.rgn
Flash RGN
- Steps 5-7 must be completed before the GPSr enters
Forced USB Mass Storage Mode.
- If this happens, restart the Flash RGN process.
- Disconnect all GPSr from your computer
-
Drag the gupdate.rgn
file to Updater.exe
- After the Updater window appears, select
the 'USB Device:' radio button
-
Power the
GPSMAP 66s/st off (press and hold power button ~10 seconds to force power down
if necessary)
- Connect
the GPSMAP 66s/st to your computer with a USB cable
- immediately press and hold
the D-PAD (Up) button
- When your GPSMAP 66s/st appears in the 'USB Device:' window, select 'OK'
-
Continue
holding the D-PAD (Up) button
- When the GPSMAP 66s/st displays "Software Loading",
release the D-PAD (Up) button
- The Updater
will display a download progress bar
- When the flash is complete, the updater
will display
a 'Successful Update' message
- The
GPSMAP 66s/st will restart with the new firmware version installed