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GTN 750 will not update

F

flyindoorman

Well Known Member
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My GTN 750 will not recognize the data card for updates when powered on. Anyone have any suggestions? I reloaded the databases from Garmin site and still no joy. Worked fine until trying to update today to current cycle.
 
I see Garmin selling “special” SD cards for $500…. Are those required for something, or can we just use ordinary SD cards?
 
GyroF-16 said:
I see Garmin selling “special” SD cards for $500…. Are those required for something, or can we just use ordinary SD cards?
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I just use ordinary SD cards for XI and non XI GTNs. Never an issue and yes Sandisk seems a better quality.
 
GyroF-16 said:
I see Garmin selling “special” SD cards for $500…. Are those required for something, or can we just use ordinary SD cards?
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A year ago I found that there are hidden files on the 650 Garmin cards. I reformatted a SanDisk saved the hidden files and it worked just fine. I did it for the SD size and the micro SD as well, same procedure. If you reformat, hopefully the hidden files can be found on a different (garmin) card in your inventory. G3X dont have them, not sure about others.
 
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My experience is that the Garmin Aviation Database Manager program will use any new or reformatted 32G or less SDcard adding any & all files as required. I have never used or needed a "Garmin" branded or sourced SDcard period. Always make sure you re using latest version of the DB Mgr program.
 
AZSteve053 said:
My experience is that the Garmin Aviation Database Manager program will use any new or reformatted 32G or less SDcard adding any & all files as required. I have never used or needed a "Garmin" branded or sourced SDcard period. Always make sure you re using latest version of the DB Mgr program.
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Thanks to all who addressed this.
I’m planning to add a GTN635Xi to my panel, and was dreading the thought of an additional $500 for a seemingly “required” Garmin SD card.
I suspected that Garmin did something to ensure that only their “special” cards would work in GTNs.
 
Problem solved. Even though it had not been an issue in the past it would not update while in the hangar.
Rolled it out for clear view of the sky and it updated soon as I powered up and it found satellite's
Randy
 
I'm thinking something else changed that you are unaware of, in my experience - when an SDcard with new DB's is placed into the unit (always with power OFF), as soon as the unit powers-up the DB is copied from the card to the unit within seconds... long before a Sat Acq could have taken place either inside or outside of a hangar. You can verify this with Garmin experimental support at the contacts listed on this form. Just my 2cents.
 
Sandisk 32GB cards work great.

Edit: it occurs to me that we have the 650 Xi, not sure if that is significant in SDcard compatibility or not.
 
I have had this issue as well, resolved by rolling out of the hangar. I think it has to do with acquiring date/time information from the satellites, not specifically the position of the aircraft, so that the GTN knows to advance to the next database cycle. This was confirmed by a call with Garmin. An alternative way to do it was to hold the home button while powering up the GTN to enter the configuration mode, and push the update manually. I'm not sure if it's related or not, but I also get the "low internal clock battery" warning on my GTN.
 
(Eye-roll). I am reminded of the scene from Monty Python -"The Holy Grail" where they are trying to determine whether or not Connie Booth was a witch.

I'm sure the GTN 650 didn't update correctly because - "Gasp" - the SD card was made of wood (ROFL).

ATango said:
I have had this issue as well, resolved by rolling out of the hangar. I think it has to do with acquiring date/time information from the satellites, not specifically the position of the aircraft, so that the GTN knows to advance to the next database cycle. This was confirmed by a call with Garmin. An alternative way to do it was to hold the home button while powering up the GTN to enter the configuration mode, and push the update manually. I'm not sure if it's related or not, but I also get the "low internal clock battery" warning on my GTN.
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Then there is this -- Yes, the RTC/CMOS battery keeps the current time so the GPS engine knows "where" to look in order to build the almanac. Without a valid time, it can take upwards of 25 minutes TTFF and without accurate time it doesn't know if the old data has expired and the new data isn't....
 
bjdecker said:
(Eye-roll). I am reminded of the scene from Monty Python -"The Holy Grail" where they are trying to determine whether or not Connie Booth was a witch.

I'm sure the GTN 650 didn't update correctly because - "Gasp" - the SD card was made of wood (ROFL).
Click to expand...

A DUCK! :)🦆
 
Probably would have saved some head scratching if you had revealed initially that your internal battery was dead.
 
dmattmul said:
And yet you reported your internal battery dead in an earlier post and then "EDIT" your previous post?
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NO SIR I did not ever state my battery was dead that was someone else that replied that had experienced the same problem.
My post has noy been edited since I posted
 
flyindoorman said:
NO SIR I did not ever state my battery was dead that was someone else that replied that had experienced the same problem.
My post has noy been edited since I posted
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Yes, you are CORRECT, it was posted by ATango the issue. Maybe he is telling us of an issue? You should not need to get GPS acquisition to update a GTN but maybe someone more knowledgeable than me should answer this, please. My apology!
 
dmattmul said:
Yes, you are CORRECT, it was posted by ATango the issue. Maybe he is telling us of an issue? You should not need to get GPS acquisition to update a GTN but maybe someone more knowledgeable than me should answer this, please. My apology!
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No worries, first time I had experienced it as well. I usually update a week before its needed this time was about six weeks between updates but should noy have made a diffference.
 
dmattmul said:
I just use ordinary SD cards for XI and non XI GTNs. Never an issue and yes Sandisk seems a better quality.
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Agree,

Legacy Garmin documentation specifies the use of SanDisk or Toshiba SD Cards

Furthermore, experience suggests that microSD-to-SD adapters are a common point of failure.
Users should exclusively use standard SD cards rather than adapted microSD media
 
I have used USB to SDcard adapters for years without issue on various Windows PC XP through 11, also used internal slot SDcard reader/writer without issue. Just my experience.
 
As I understand it the non Xi have to have a certified Garmin SD-card in the slot during flight on a certified aircraft.
But a Xi unit may use any SD-card. Card is not required to be in the slot during flight.

Good luck
 
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