Garmin GNC300XL issue route wpt locked

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Cheapjeep78

Filing Flight Plan
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Kitfox4
I bought a used gnc300xl for my experimental just for direct to flights. After installing, radio works and can swap between channels but after the western us screen comes up and I hit enter, route wpt locked comes up on screen and no buttons work except the radio swap and msg. I live in Tennessee and card is out of date anyways but don't want to waste money updating card if this route wpt locked error isn't related to card expiration. Has anyone seen this? Any way to remove all way points like factory reset? First plane, first aviation garmin. Any help appreciated.
 
Anyone in west Tennessee that has an updated card I might could test would also help a lot.
 
Cheapjeep78 said:
don't want to waste money updating card if this route wpt locked error isn't related to card expiration
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It's not (sort of). It has to do with a waypoint in a saved route that doesn't exist in the current database.

Buttons not working has nothing to do with that error. Probably dirty/failed button contacts, or some other related hardware failure.

Do you have a pilot's manual for it? If not, get it here: https://support.garmin.com/en-US/?productID=101&tab=manuals

Installation manual is here: https://www.manualslib.com/manual/2442234/Garmin-Gnc-300.html
 
Don’t forget the 300XL has such a small capacity card that maybe 15 years ago it started needing two cards for all the data. Plus the cards aren’t data “mules” carrying the data to the device for internal storage: the card IS the storage, so a card with the proper data, current or not, must physically be in the box. I carried three cards for mine: one east, one west, and one spare with whatever side I thought I’d use most that cycle.

On Jeppesen, IIRC, you could subscribe to East, West, or both. I did both since we’re in Texas (there’s decent overlap in coverage).

Hack: to make the duplicate card, I’d put one in and update it but pull it out when it started the Verifying phase. That seemed to trick the downloader into thinking it had not downloaded it, so the second card then went in and I then had a backup. So says some people could update a whole bunch of their friends’ cards off of one script this way…

My suspicion is your waypoint is outside the range of the database you have on the card (or you’re not leaving the card in). Buy one update for each half of the US and I bet you’ll be good. And I bet you can find extra cards on eBay. The cards didn’t last forever, by the way. I’d keep a spare since it’s bricked without a working one.
 
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Llewtrah381 said:
Don’t forget the 300XL has such a small capacity card that maybe 15 years ago it started needing two cards for all the data. Plus the cards aren’t data “mules” carrying the data to the device for internal storage: the card IS the storage, so a card with the proper data, current or not, must physically be in the box. I carried three cards for mine: one east, one west, and one spare with whatever side I thought I’d use most that cycle.

On Jeppesen, IIRC, you could subscribe to East, West, or both. I did both since we’re in Texas (there’s decent overlap in coverage).

Hack: to make the duplicate card, I’d put one in and update it but pull it out when it started the Verifying phase. That seemed to trick the downloader into thinking it had not downloaded it, so the second card then went in and I then had a backup. So says some people could update a whole bunch of their friends’ cards off of one script this way…

My suspicion is your waypoint is outside the range of the database you have on the card (or you’re not leaving the card in). Buy one update for each half of the US and I bet you’ll be good. And I bet you can find extra cards on eBay. The cards didn’t last forever, by the way. I’d keep a spare since it’s bricked without a working one.
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OP, this is your answer regarding the waypoint locked. I fly in Puerto Rico so I use the Latin America database. If I plan a route in the states, there is a very good chance that the saved route will show waypoint locked. If I put my east US card in, no problem.

The other issue I’ve run into is that if you put a fresh card in a gps, it’s locked to that gps. So if you then try to put it in another one, you’ll run into issues. I don’t remember the symptoms being exactly like you describe, so probably not the issue
 
Wrench978 said:
The other issue I’ve run into is that if you put a fresh card in a gps, it’s locked to that gps. So if you then try to put it in another one, you’ll run into issues. I don’t remember the symptoms being exactly like you describe, so probably not the issue
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That MAY be true for the 300XL but I’m pretty sure it’s not - they’re a pretty old GPS. I think that reality began with maybe the 430/530s or something. But good point - it’s something to be aware of.

If that’s the case, it’s possible one could try reformatting the card on a PC and thereby reset it - not sure.
 
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Llewtrah381 said:
That MAY be true for the 300XL but I’m pretty sure it’s not - they’re a pretty old GPS. I think that reality began with maybe the 430/530s or something. But good point - it’s something to be aware of.

If that’s the case, it’s possible one could try reformatting the card on a PC and thereby reset it - not sure.
Click to expand...
I had a 2nd 300xl that I was messing with and when I put a newly updated card in that one, I couldn’t use it in my installed unit. Maybe it was an error, but it seemed like it was intentional. I could be wrong though. I’m certainly no expert on these GPS’s
 
Wrench978 said:
I

I had a 2nd 300xl that I was messing with and when I put a newly updated card in that one, I couldn’t use it in my installed unit. Maybe it was an error, but it seemed like it was intentional. I could be wrong though. I’m certainly no expert on these GPS’s
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You have more real-world experience than I do on that.
If it doesn’t work, I still wonder if a reformat would fix it. You’d still need to buy/get an update after reformatting but seems like there’s little to lose.
 
Llewtrah381 said:
Don’t forget the 300XL has such a small capacity card that maybe 15 years ago it started needing two cards for all the data. Plus the cards aren’t data “mules” carrying the data to the device for internal storage: the card IS the storage, so a card with the proper data, current or not, must physically be in the box. I carried three cards for mine: one east, one west, and one spare with whatever side I thought I’d use most that cycle.

On Jeppesen, IIRC, you could subscribe to East, West, or both. I did both since we’re in Texas (there’s decent overlap in coverage).

Hack: to make the duplicate card, I’d put one in and update it but pull it out when it started the Verifying phase. That seemed to trick the downloader into thinking it had not downloaded it, so the second card then went in and I then had a backup. So says some people could update a whole bunch of their friends’ cards off of one script this way…

My suspicion is your waypoint is outside the range of the database you have on the card (or you’re not leaving the card in). Buy one update for each half of the US and I bet you’ll be good. And I bet you can find extra cards on eBay. The cards didn’t last forever, by the way. I’d keep a spare since it’s bricked without a working one.
Click to expand...
I have 2 cards, just need to update them. Got a brief description of how and where? I live in west Tennessee and will stick to mainly Tennessee, Alabama, Missouri, and Mississippi. Assume east should cover that. So do I need to buy a jeppesen skybound device and update myself or anywhere you can send these to get an update to test?
 
Llewtrah381 said:
Don’t forget the 300XL has such a small capacity card that maybe 15 years ago it started needing two cards for all the data. Plus the cards aren’t data “mules” carrying the data to the device for internal storage: the card IS the storage, so a card with the proper data, current or not, must physically be in the box. I carried three cards for mine: one east, one west, and one spare with whatever side I thought I’d use most that cycle.

On Jeppesen, IIRC, you could subscribe to East, West, or both. I did both since we’re in Texas (there’s decent overlap in coverage).

Hack: to make the duplicate card, I’d put one in and update it but pull it out when it started the Verifying phase. That seemed to trick the downloader into thinking it had not downloaded it, so the second card then went in and I then had a backup. So says some people could update a whole bunch of their friends’ cards off of one script this way…

My suspicion is your waypoint is outside the range of the database you have on the card (or you’re not leaving the card in). Buy one update for each half of the US and I bet you’ll be good. And I bet you can find extra cards on eBay. The cards didn’t last forever, by the way. I’d keep a spare since it’s bricked without a working one.
Click to expand...
I have 2 cards. I'll update if I can verify unit works correctly first. If not I'll end up buying newer. Hope someone that has a card outside their current area can put wrong card in and see if it allows buttons besides radio related buttons to work. That would get me started in the right direction. Thanks for replies. Good group of guys in here.
 
Add: even with perfectly working and updated cards, I’m pretty sure you’ll get the same message if you create a flight plan that extends beyond the boundaries of the card you have physically in the box at the time. For really long flight plans that do so, I’m pretty sure you’ll need to create several plans that each stop and start within the bounds of the area on the card you’re using. The East and West areas overlap a good bit, so that’s not too hard.
 
Cheapjeep78 said:
I have 2 cards, just need to update them. Got a brief description of how and where? I live in west Tennessee and will stick to mainly Tennessee, Alabama, Missouri, and Mississippi. Assume east should cover that. So do I need to buy a jeppesen skybound device and update myself or anywhere you can send these to get an update to test?
Click to expand...
Jeppesen is the only ones who sold the updates when I got rid of mine a few years ago. You’ll need the blue Skybound G2 adapter (https://shop.jeppesen.com/All-Produ...a-Hardware/Skybound-G2-USB-Adapter/p/10533225) plus the Jeppesen Distribution Manager (JDM) software for whatever desktop device you’re using plus a subscription to the data itself. Looking online, the last part looks tricky. You may need to contact Jeppesen sales to ask about that. https://ww2.jeppesen.com/navigation-solutions/avionics-solutions/garmin/
 
Update directions are as noted in above posts. Though, it sounds like you're using this GPS for VFR flights only, if that is the case, you can just do a one-time update for less cost than a full year's subscription. ( At least, that used to be the case, it's been a few years since I've done one of those.)
 
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