Quote Originally Posted by jamesbxue View Post
Hello, I am new to the forum and would appreciate some help on my Nuvi2589lmt, Software version 8.50, HWID 1947
1947 is C4 firmware. "Non-C4" is HWID 1758. Could it be you're trying to flash the wrong firmware?

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After connecting the device to a wall charger and restarting the device, it would have the license screen, alter screen and load map. To make things worse, the map also was corrupted during the Garmin Express update, and the device shows “Cannot unlock maps” and “Maps are corrupt and cannot be used.” Then I got a prompt: “Updates – There are additional updates that require the device to restart. This may take several minutes. Restart now?” After clicking Yes, it will show a quick screen of installing update files with full green status bar, then shuts off. I normally can’t press the power button to power it on again from that point. A few occasions I can power it on right after, it will get into a screen showing Garmin Logo and a short stretch of green status bar, with message “Installing update files. This may take several minutes”. It then stuck there for 4-5 hrs, and the status bar won’t change at all. At the end it just shuts off, and no change is made.
First try to clear non-volatile memory. On the 'Map' screen tap the speed field and then hold the center of the speedometer for several seconds to enter the Diagnostics Page, tap Developer Info and scroll down and tap Nonvol Statistics, tap the three menu bars and choose 'Clear Nonvol'. Be aware that you may loose favourites and navigation history. If that doesn't cure it then read on. It should be done anyway before going further.

Currently, I can still connect the device to PC occasionally. My PC and Garmin Express can see my device, including the .System folder as I have changed it to Mass Storage Mode. I haven’t tried the Preboot mode yet as the device doesn’t seem to boot on its own when pressing the power button. I have read the post on GarminCure3 and How to unbrick step by step.
Cure fw is only used to re-enble Mass Storage Mode on a bricked device to allow removal of corrupt files or a re-format. You don't need it as the device still has MSM.

I have called Garmin support, and they think it might be a mixed issue of power module and software.
AKA 'Stock BS answer F'. I think it's not a power problem quite frankly. It may however be a firmware problem but probably not in the way he was referring to it.

The key point seems to be the device won’t start to run the loaded software on its own, and there is not much they can do. I would like to try the unbrick steps but would appreciate some suggestions first.
It's not able to load from the later GCD file which is perhaps the corrupt file. Start by removing from .System that file, it's named 'gupdate.gcd', to see if it stops misbehaving. If you still have problems then reformat the internal memory using only RMPrepUSB, you'll find the link to it in the initial post of Kunix's Cure3 thread.

Before replacing the GCD file be absolutely certain which chip version you have matches the HWID of the intended firmware.

Report back if you still have problems, there is more can be done but let's see how you go first with GCD removal or a re-format. Don't use anything but RMPrepUSB or the format may make things worse.