GPS/Tracking failure - ideas?

I've had very good function from my InReach Explorer+ so far, but had a problem yesterday. Any ideas or input will be valued.

I was using the unit while undertaking a long-ish (10 hour) drive across country, so that family could keep track of progress. As I've been waiting for stock to arrive of the powered vehicle mount, I had the inReach on the dashboard of the vehicle, with only the windscreen obstructing a clear view of the sky. I've used it plenty of times like this without any issues, and the route through which I was driving was 98% wide open spaces, with the last 2% being mountain passes - territory in which my otehr GPSs and vehicle nav system have no trouble maintaining a lock.

At some point about 3 hours before the end of the drive, the device stopped updating to the tracking, and seems to have lost GPS fix. See the photos attached. It then reconnected when I turned it off and back on again at home.

Has anyone seen this behaviour? ciq.forums.garmin.com/.../1241080.png ciq.forums.garmin.com/.../1241081.jpg

0 twolpert over 8 years ago

The real question is whether you actually lost lock or lost connectivity with the Iridium network. Can't actually tell from the maps.

It's difficult to imagine either being a problem when sitting on the dashboard. There are a couple of things you can do to check. First, look at the history page on the unit. This will show every "sent" point which the unit recorded. If you have points in the area of the gap, then the issue was not the fix - it was connectivity to send the points. I am not sure about the Explorer+, but earlier models had a limited amount of storage for recorded points that had not yet been sent because of lack of connectivity. Once the storage is full, the unit discards the oldest point to make room for each new point as it is recorded. This can result in a gap in the sent track points even when connectivity is restored.

Note that when the unit is having trouble sending, the red LED should be blinking. In addition, you should see the data transfer icon (the up/down arrow) flashing periodically in the status bar. Eventually, I believe that transfer icon will change to something which includes a fat exclamation point.

You said that you power-cycled the unit. When you turned it off, did it warn you that there were unsent track points? If so, how many? This is another indication that the unit lost connectivity rather than (or in addition to) losing the fix. Also, remember that ignoring that warning message will cause loss of the pending points. (I believe they still show up in history, but I can't say I've ever checked.)

The other thing that you can do is to connect the unit via USB to your computer and do a wired sync. This is will transfer any track points which are on the unit but not on the web site. If you were also logging track points (in addition to sending them), it will also transfer the logged points. If the missing segment fills in after you sync, then it was connectivity rather than loss of lock.

Iridium connectivity is considerably more sensitive to unit orientation and directionality than the GPS fix. Typically, only one Iridium satellite is visible at any one time in any particular location. If the satellite happens to be "behind" your vehicle, you will not connect with the unit sitting on the dash. The roof of the vehicle is a very good shield. I don't know enough about the Iridium constellation to know if that would be likely to be a persistent condition if you are traveling in the same direction for several hours. Anecdotally, I do know that I sometimes lose connectivity with the unit sitting in the cup holder between the front seats.

0 WILDMEDIC over 8 years ago

Definitely lost GPS tracking - there are no track points recorded on the unit (despite being in tracking mode for the entire duration), and there was no message to upload unsent points when I power cycled the unit. I don't think the Iridium connection was the issue - I think the GPS lost lock and stopped tracking for some reason.ciq.forums.garmin.com/.../1241430.jpg

0 twolpert over 8 years ago

Even if your pic was large enough to see, the maps don't prove anything unless you've done a wired sync. However, the lack of recorded points on the unit is pretty conclusive. Either it spontaneously stopped tracking or it lost lock. There's no reason for a loss of lock if it was sitting on the dashboard. But either way, I'd call tech support. I wouldn't have faith in the unit for back country/safety use until it's been serviced.

0 WILDMEDIC over 8 years ago

Weird - the photos were full-screen captures when I uploaded them, but it seems as if the forum has cropped down to thumbnails.

I have the same interpretation as you - the device lost lock, for no apparent reason.

I'll ask Garmin to comment.