How long should the M2 take to charge? Mine went from 14% to 72% in 6 hours!

twolpert, thanks for your input but I'm not going to open an RMA as the product is brand new, I don't know how it works in the States, but here in the UK if a product is faulty from the off, I can send it back (in this case, Amazon).

I just wanted to get an idea of what to expect in terms of battery life, Hiking Emergency Beacon reckoned on two weeks give or take, one week would probably do me.

So now the test is being repeated with full sky view and no movement. So that's why I was asking for any anecdotal info on what time people were getting on the unit.

In addition, if I were to send it back, I'm assuming that I'd have to cancel the subscription (£15) which I will lose if they can't transfer it to another unit, so you see, I'd like it to work OK as it will cost me to find out otherwise.

It was only because the no sky view test resulted in 11 to 12 hours battery life, which I thought was very low even given the strain the unit was under to lock on to staellites.

Thanks Edvard, as per your comment on hikingemergencybeacon, I'm doing a static window test, and that's all it will test.

I'm only doing this to establish I haven't been sold a dud unit-battery wise, I'll be more than happy if it turns out to be more or less as they say in the test video.

That's all.

However, I can see there's other factors at play here, for instance, I live in the city, and my window will not see a horizon so that might have an impact if it can't see satellites.

I took your advice and checked : Navigate > GPS coordinates it came up with two lots of coordinates both with 000.000.00 refrence .

I'm assuming that it can't see the satellites? And this in turn will affect battery life as twolpert mentioned?

If you see coordinates, you have a location. The displayed format can be changed in settings.

I did the following test last night:

Charged an inReach Mini 2 to 100%. Placed it standing in a clothing cabinet. The device had no line of sight to any window, concrete walls all around, 3 floors above and outside the building there’s a park with large, thick tropical trees.

My standard settings with GNSS enabled and device connected to Garmin Explore iOS app. The device never moved from its location on the shelf, a couple of meters from the outer wall.

It soon started giving error messages, the triangle symbol and chirping because unable to check messages from Iridium.

One thing worth noting about the iOS Garmin Explore app, is that it does not show any device notifications, such as error sending or no-GPS fix before send.

The spinner top-right in Message tab just keeps rotating.

I’ve suggested to Garmin that as a minimum the app must have a time stamp for last successful message check. That is very relevant info for the user. 

Today this time can only be seen on the device, but not while a message check is ongoing – and there is no way of cancelling a message check. The app also does not show battery status.

A couple of hours later, I visited my share.garmin.com/mapshare page and sent two messages to the device. One with a local mobile number as sender and one with a Norwegian number. Then I went to sleep.

In the morning both messages had been received. I replied to the messages from the Explore app and within 30 minutes they were sent to recipients as SMS, including position and inreachlink.com for map.

 After 14 hours the battery charge was 25%.

Hello semmyroundel Leaving an inReach device on and inside will quickly drain the battery every time. It will continually try to communicate with satellite and fail therefore causing the battery drain that you are experiencing. To fully test the battery life you will need to be outside with a clear view of the sky. How Long it Takes to Send or Receive inReach Messages // Improving the Battery Life of Garmin inReach Products.

Hi Leslie, yes I know all that, but it's in view of the sky in a plate glass window north facing, and I fully understand that it will try a mail check once an hour but that's all it's doing nothing else, no tracking messages etc.

THE SOLE PURPOSE of doing this test is to ascertain if the battery is ok as there was a suspicion that it might not be, I understand that it will use a lot more battery inside the house, but to quantify that is what I'm trying to do-you see if there is a problem with it, trying it outside on the trip will be too late to get it changed out.

I can't leave it outside in the garden for a day-it might get stolen.

I've been advised to fully test it before going on a trip with it, but that can only be done apparently in the open air.

With regard to it not getting satellites indoors, I performed a test check and it said test succesful after only 6 minutes-I'm assuming that meant a test to see if it could access iridium satellites.

The ability to work indoors is hit and miss (mostly miss). If you have it on a windowsill with 180 degree sky view, it will work. However, there will be some oddities.

First off, your apparent position will drift. This is a result of the restricted view of the GPS constellation. If you let it site in a north-facing window and track, you will see long, fast excursions mostly in a north-south direction.

Secondly, your Iridium communication may be a bit hit and miss. The restricted view also affects the visibility of the iR satellites, as well as the time for which they are visible overhead. In my experience, this does not prevent Iridium communication. But I would not be surprised to see some delays and some additional battery drain.

Once you get away from the windowsill, any iR (or GPS, for that matter) reception is going to be the result of multipath reception - satellite signals bouncing off hard surfaces (walls, floors, ceilings). This is much less likely to be effective for iR communication because the unit needs to bounce transmitted signals. Not to say that it will never work, but it is going to be hit and miss.

The best suggestion I have for testing the battery in your situation is that windowsill test. Set the unit up to send track points (let's say at 10 minute intervals). Charge it up, set it on the windowsill, and let it sit all day. Check the battery after 8 or 10 hours. If you like, you can check the track points on MapShare occasionally. The occasional GPS "drift" is actually a good thing for this test. Normally, a stationary iR device automatically falls back to "one sent point every 4 hours" until it senses movement. Then it returns to the configured send interval. With a clear sky view, you'd see one or two 10-minutes point, then a point every 4 hours. With the GPS drift, you'll see "occasional" points at various apparent locations. NOT one every 10 minutes, but certainly more often than every 4 hours. If you view this on the map, the result will be the "spiderweb" (similar to what you get with multipath reception in general). The lines connecting those points will be mostly north-south.

Does that make sense?

Thanks twolpert, perfect sense, clarifying the unit's ability to track satellites where the uninitiated like myself that thought they were static. Cheers.

I do think so far that the amount of battery usage is comensurate with the constant searching for a satellite fix, but I haven't completed the window 24 hr test.

If for no other reason than to check if a battery is likely to be faulty or not, this exercise will have been worth it as someone else looking at my input can assess if their drain was similar.

I will post the drop in percentage tomorrow.

Window test with no activity demanded of the unit 25% down in 24hrs. I hope you're all correct in that it'll last two weeks outdoors with little tracking, I have my doubts.

It depends on how you organize your daily use. I do not use mine for logging or navigation, only for offline communication and to have as backup.

If out walking in nature, I have the device turned off in my backpack hip pocket.

In the morning, lunchtime and for evening rest I send check-in messages.

During the day I send the occasional location ping, especially when traveling onto a new direction or trail. If in motion I would take the Mini out, turn it on, clip it to my shoulder strap, click down to coordinates page, and let it rest for a while.

I communicate with the device via the iOS Explore app. On demanding route sections or in rough weather I sometimes leave the unit on for extended periods. If not, it’s turned off and placed back in a pocket until next use.

Last fall I did this routine for 40 days in the Norwegian mountains on one charge before battery was critically low.

That included hundreds of check-in messages, a bunch of weather reports, free-text messages, and times when the device was on for hours.