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  1. #1
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    Default Nuvi 58LMT "can't unlock maps".

    I've got a Garmin nuvi 58LMT which worked flawlessly until a couple of days ago. I used Garmin Express to update it as I'd done many times before, no errors reported.

    After disconnecting the device it seemed to take longer than usual to power up. When it did I get a message about no detailed maps available and then that it can't unlock maps.

    I've done some research into this.

    Reinstalling maps doesn't help. Everything seems to work fine but same error.

    Factory reset: nope same error.

    I switched the device from MTP to mass storage so I can see the hidden .System folder. Wish I'd known about that before so I could back everything up.

    Internal storage says 5.55GB free so it's not full up. Added a 32GB SD card (FAT32) just in case. It's visible but no data is written to it when I reinstall the map.

    Only oddity I can see (which may be nothing) is that myMaps on the device give me one option "CN Europe NTU 2026.20 Foursquare" and Garmin Express reports "City Navigator UK & Ireland 2026.20" maps (I'm in the UK).

    Chat with Garmin support said basically "it's a brick have a discount on a new one".

    I suspect it's a misconfiguration or a corrupted file but not sure what to try next.

    Any ideas?
    Last edited by stevex; Yesterday at 04:47 PM.

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  3. #2
    Garmin/GPS Systems GMod. Nuvi 58LMT "can't unlock maps".
    Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".
    Neil's Avatar
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    The message "Can't unlock maps" indicates that there's a detail map on-board which has at least one locked map tile in the *.img file. In your case, being that it's an LM (Lifetime Maps) device, its map entitlement should be supplied 'locked' but with the appropriate UNL & GMA files to allow the device to read and use the maps.

    Although you don't specifically mention this, the tone of your post seems to indicate that once it does boot up fully it can operate and navigate fully normally, it that so?

    Please also advise the details of all IMG files showing in the internal memory's ".System" folder, and if present, also in its "Map" folder.
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  4. #3
    VIP Master Nuvi 58LMT "can't unlock maps".
    Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".
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    All is not lost.
    If you use your SD card as a clone of your device you should be able to download all the update files.
    Make a copy of your garmindevice.xml from your device ,create a folder on the SD card called Garmin and paste it into it.
    Disconnect your device from your PC and plug in the SD card.
    Use Garmin Express to update the SD card clone and you should end up with a .system folder with the update.
    You can then copy/replace the files in the system folder on your device from the SD card
    Code:
    Please Login or Register to see the links
    Spoiler: .system image
    [Only registered and activated users can see links. ]

    From you file list below it looks like the UK & ROI map update happened and the FW was also updated ,most properly a corruption occurred of the gmapprom.img,gmapprom.unl or gmapprom.gma

    What you are seeing/describing is the base map gmapbmap.img without any detailed map.
    Last edited by Garman_Nuvi; Today at 01:37 AM.

  5. #4
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    When it powers up a box appears saying "Detailed maps are required for routing. No detailed maps were found on this device". After a few seconds that box disappears and I get a second box saying "Cannot unlock maps" with OK.

    It can navigate but not normally. The map displayed now longer shows street names just major road names.

    I've attached the complete directory listing as a zip.
    Attached Files Attached Files

  6. #5
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    I tried that with an SD card just containing garmindevice.xml. Garmin Express saw it and wrote the files you listed above to it. I then copied all those files to my device (making a full backup first) overwriting those already present. I also removed some extra files in some of those folders.

    Unfortunately when I power it up the same happens as before. Says no detailed maps present and can't unlock maps.

  7. #6
    Garmin/GPS Systems GMod. Nuvi 58LMT "can't unlock maps".
    Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".
    Neil's Avatar
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    The messages "No detail maps present" and "Can't unlock maps" are somewhat inconsistent. Looking at your device contents, the only detail map present in the .System folder is "gmapprom.img" with size of 711,524,352 bytes (~679 MiB) and in .System\Map is one of 162,926,592 bytes (~153 MiB) named "D4935310A.img". They are likely to be your UK detail map and the Foursquare i suppose. You should open them in [Only registered and activated users can see links. ] to identify them and check for errors.

    The other possibility is that one of the "old" GMA or UNL files from an earlier version map is interfering with reading of the current detail map. You could try removing everything from the Map folder except these:
    Code:
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    Keep a copy of the GMA & UNL files you remove of course.

    You could also try removing all the present detail maps and their associated GMAs and UNLs then replace them on the device in their proper locations with the files you downloaded from GE via the "nuvi clone" SD.
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  8. #7
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    Yes gmapprom.img identifies as the UK map and lists a lot of regions in it under the "name" column. The other shows as Foursquare but the name column is blank.

    I use GMapTool to show info and details for both. No obvious errors (as in a line containing the word "error"). Everything is listed as locked. Anything in particular I should be looking for? Would posting the full log details help?

  9. #8
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    In your case (regardless of the LMT), I would use patched sw and see what happens.
    It's not that I'm so smart, it's just that I stay with problems longer. (Albert Einstein)

  10. #9
    Garmin/GPS Systems GMod. Nuvi 58LMT "can't unlock maps".
    Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".Nuvi 58LMT "can't unlock maps".
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    @janch
    Yes that'll work for sure unless it's a corrupt IMG (not identified in GMAPTool though) or he has a physical flash problem (unlikely). Regardless, because it's an LM device i'd prefer to sort it out without reverting to patching if possible ....
    Nudge, nudge, wink, wink ... you know the problems that big-bang's patcher caused us in 2017 ...

    @stevex
    Did you try this?:
    The other possibility is that one of the "old" GMA or UNL files from an earlier version map is interfering with reading of the current detail map. You could try removing everything from the Map folder except these:
    Code:
    Please Login or Register to see the links
    and/or this?:
    You could also try removing all the present detail maps and their associated GMAs and UNLs then replace them on the device in their proper locations with the files you downloaded from GE via the "nuvi clone" SD.
    'Thanking Posts' are banned. To thank someone, and/or to see hidden links and content, use the [Only registered and activated users can see links. ] button below left of the helpful post then refresh your browser [F5 key]. 'Thanking Posts' are banned.
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