GPSMAP 66i - Recent Threads

Track not in Track Manager.

1992102 — Wed, 06 May 2026 00:16:11 GMT

Sorry if I am posting in the wrong place. I was unable to find an area for the Garmin GPSMAP 65s which is what I have. I recently synced a collection to my device. The track I want to load is in the Collection Manager but not in the Track Manager. Why not? Is there a solution to this problem? - Scotty

P.S. Updated device software today.

how to skip inrich activation

3290483 — Sun, 29 Mar 2026 04:44:50 GMT

Hello,

Because of some problems with the newest firmware, I choose 6.30 for my 66i. Every time turning on, it want me to activate the inRreach. Is there a way to avoid it?

Thanks.

RE: how to skip inrich activation

skyeye — Sun, 26 Apr 2026 13:33:02 GMT

InReach devices need to be activated in order to operate. Non activated device is not very much useful.

What do you want do with an InReach device which is not activated?

RE: abnormal infromation in "Recording Controls" and "Trip Computer"

Former Member — Sun, 15 Mar 2026 00:11:46 GMT

calibrate what right?

abnormal infromation in "Recording Controls" and "Trip Computer"

Former Member — Mon, 20 Oct 2025 11:07:06 GMT

Good evening, everyone.

I encounter some problems with GPSMAP 66i.

Have you ever encountered such problems?

RE: abnormal infromation in "Recording Controls" and "Trip Computer"

9695440 — Wed, 17 Dec 2025 15:44:20 GMT

From my experience, this usually happens when the GPS signal isn’t strong or the device isn’t calibrated right. I just check the signal and maybe restart it, and it mostly works fine.

RE: Setup - Recording - Auto Start

skyeye — Wed, 19 Nov 2025 20:16:21 GMT

but does it not end the recording when switched off?

Setup - Recording - Auto Start

Former Member — Sun, 09 Nov 2025 14:05:29 GMT

Good evening, everyone.

Track Settings Explained on the GPSMAP 66i/67i/86i/86sci:

Auto Start

When enabled, the handheld will start a new recording automatically when the previous recording ends.

Is it true? It seems to me that it starts when it is powered on.

Error trying to update software and map

1704604 — Fri, 07 Nov 2025 20:09:00 GMT

I am receiving an error while trying to update the software and map through Garmin Express. I have factory reset the unit, it connects but will not even begin the update without a red error message.

Software Version after Master Reset

Former Member — Fri, 07 Nov 2025 02:43:10 GMT

Good morning, everyone.

After Master Reset, the Software Version of my 66i is 10.20, the latest version, not the factory default.

How about your 66i?

RE: Software Version after Master Reset

JungleJim — Fri, 07 Nov 2025 06:16:35 GMT

That’s normal, a factory reset will clear out user data and settings. It will no revert the installed firmware to a previous version.

RE: Auto Save - Daily doesn't work?

reinhardz — Sat, 18 Oct 2025 23:00:37 GMT

Ah, thanks!

Auto Save - Daily doesn't work?

Former Member — Tue, 14 Oct 2025 02:25:56 GMT

Good morning, everyone.

I tested "Auto Save - Daily," but there is only "Current Activity" in "Recorded Activities" and nothing in "Saved Tracks."

I tested it this way:

Setup - Reset - Delete All;

Setup - Recording - Advanced Setup - Auto Save - Daily;

Setup - Display - Battery Save - On.

Software version is 2.90.

Move the 66i outdoors one day evening, the next day morning, I get the result above.

Where is the problem? What should I do to see the result of "Auto Save - Daily?"

Thank you so much in advance.

wrong "date modified" of .fit and .gpx

Former Member — Fri, 17 Oct 2025 00:29:53 GMT

Good morning, everyone.

What I do as below:

reset - delete all

setup - recording - record method - time; interal 3 seconds; advanced setup - auto save - daily.

20251016 11:29 local time to start recording; 16:44 lose signal; 17:04 power off; 20151017 06:37 power on.

Then the "date modified" of .fit and .gpx is 16 May, 2025.

Is it a bug?

RE: wrong "date modified" of .fit and .gpx

Former Member — Sat, 18 Oct 2025 02:59:02 GMT

When there is signal, the date and time is October 18, 2025 10:20AM; When signal lost, it changed to May17, 2025 07:26.

I've already contacted Garmin.

Have you ever encountered such a problem?

RE: Auto Save - Daily doesn't work?

Former Member — Fri, 17 Oct 2025 23:37:48 GMT

Two days should be separated. If record contunuously through midnight, it is considered one day.

RE: Auto Save - Daily doesn't work?

reinhardz — Fri, 17 Oct 2025 21:57:41 GMT

How?

RE: Auto Save - Daily doesn't work?

Former Member — Thu, 16 Oct 2025 23:23:10 GMT

Resolved.

RE: Ascent - Average: The average vertical distance of ascent since the last reset.

skyeye — Tue, 14 Oct 2025 09:36:29 GMT

I would first ask: how is anything vertical measured at all?

Air pressure will definitely depend on the weather and this has as we know not much constants

Ascent - Average: The average vertical distance of ascent since the last reset.

Former Member — Fri, 03 Oct 2025 06:29:24 GMT

Good afternoon, everyone.

GPSMAP 66i manual, page 46, Data Fields:

Ascent - Average: The average vertical distance of ascent since the last reset.

Would you like to explain how it is calculated?

Thank you in advance.

RE: Vertical Distance to Destination

skyeye — Tue, 14 Oct 2025 09:30:53 GMT

I would first try to figure out how this is measured in first place. GPS altitude is not very precise, so barometric preasure can be used. But this is dependeing on the changes of air pressure and also wind strength etc. So there can not be any kind of absolut numerical data for this.

Vertical Distance to Destination

3108822 — Tue, 30 Sep 2025 03:45:40 GMT

Any suggestions to fix incorrect Vertical Distance to Destination readings? When I'm hiking, the field displaces incorrect elevation distances, for example, showing a positive gain when I'm on a peak and destination is below at the trailhead, or vice versa showing a negative distance when I'm heading to higher elevation.

MapShare issues

5941231 — Sat, 27 Sep 2025 20:02:42 GMT

My Gpsmap 66i stopped uploading tracks (in fact all data) to MapShare. I have reset the device several times and verified all settings in Garmin Explore. My subscription is active. The device Bluetooth and Wi-Fi settings are turned off to save power.

RE: MapShare issues

jlg2 — Mon, 13 Oct 2025 21:13:03 GMT

MapShare has worked well for me including as recently as August 2025. Like you, I don't carry a smartphone when on foot in the backcountry. I assume you are aware of the multiple and easy-to-overlook settings on the Explore website that all have to be correct for your Iridium track points to appear.

The word "uploading" in your original post was a little equivocal. From the context, I think it's clear mean track points sent through the Iridium network and not tracks uploaded later through an Internet connection.

RE: Ascent - Average: The average vertical distance of ascent since the last reset.

jlg2 — Mon, 13 Oct 2025 20:56:13 GMT

You asked a good question. It matters to anyone using the device on multi-day outings. I don't think anyone here or even at frontline support has access to the algorithm.

One would expect the ascent (and decent) to be the sum of non-negative (non-positive) elevation differences between each recorded track point and its predecessor since the measurement is in something called a "Trip Recorder." In other words, total ascent should always be greater than or equal to the positive change in elevation, and total descent should always be greater than or equal to the negative change in elevation.

In my experience over all recent firmware updates (this wasn't true in the past) the device gives a close approximation to the expected value for ascents and descents recorded during a continuous track recording of up to several hours.

But there is a very common situation where the expectation fails. If you reset the Trip Recorder and then hike to an elevation that is 1000 m about the reset point, the total ascent should show 1000 m plus whatever amount you descended along the way since those descents mean repeated ascents. So when you reach the point 1000 m above your reset point, the device gives a fairly good approximation of the total ascent.

Say, for purposes of example, that the device shows 1100 m at that point and you pause recording for a long lunch and siesta. From that point on, the device will generally fail to meet the expectation of a close approximation. When you check the ascent after your nap, you'll find that you climbed as much as 100 or 200 m while you were lying on your back. The problem is that even though it's called a "Trip Recorder" and even though all other measurements freeze when track recording is paused or stopped, ascent and descent keep on incrementing upward as long as the device is on. Without direct knowledge of the algorithm, I can only assume that it is because the natural uncertainties in each measurement keep accumulating as phantom ascent and decent. If you camp overnight and leave the device on, the next day you will discover that yesterday's ascent could be a few hundred meters greater than it was when you went to bed even if atmospheric pressure did not change.

Atmospheric pressure changes are another source of error. As far as I know, that error is unavoidable. Pilots, for whom, precise altitude is important, reset their altimeters every hour or so. By my calculation, you can expect that pressure-change error to be less than 50 m/day except during weather events like swift frontal passage when the one-time error will typically be about 100 m. Unlike the aforementioned accumulated recorded errors, the atmospheric pressure changes over durations of a few days or less should all be in one direction. In other words, if the error causes ascent to be wrong, the barometric error will not ordinarily affect decent, and vice versa.

Personally (as I've often told the Garmin feedback page), I would like to see the firmware altered so that when recording is paused or stopped ascent/descent stop changing like all the other metrics in the Trip Recorder. That way, you could freeze ascent/descent when you expect to be stationary for several hours, like overnight, then resume recording when you start moving. Assuming you use the default setting to reset the pressure when the device is turned on, I believe the atmospheric pressure changes while the device was not recording would be fairly obvious in the track record since they would appear as spikes when the device resumed recording. So at least the errors from atmospheric pressure change that occur when the device is not recording would be easy to correct for.

As it is, the only way to get a good approximation of your total ascent/decent over a multi-day trek is to keep a written record of the descent/ascent numbers at the beginning and end of each stationary period and then do the math yourself.

A more general complaint of mine applies to most electronic device manufacturers. They hire documentation writers who might be good communicators but who know little about the inner workings of the devices on which they give instruction. So the documentation only gives recommended sequences of steps and leaves it to reader to figure out by inference what the device is really doing.

If anyone knows (notice emphasis) what the algorithm is for ascent and descent, I hope he'll share it. This thread would be a good place.