My iPhone GPS failed in the middle of nowhere?

No theory, but it strengthens my resolve to never depend on electronics.  I’ll always have a good compass and a water-protected map.  :)  Moisture is always a suspect when electronics go haywire, so your theory about the Garmin passes the sniff test.  Was the phone flakey in all its functions, or just the nav functions?

I’ve had no problems with GPS or Iridium satphone anywhere in Alaska EXCEPT – in 2007 I was hanging out on the Denali Highway fishing and hiking and I could not get a GPS satellite signal .  I’ve shared that info with others but never found an explanation.

Todd, my iPhone worked fine in all other respects, as did my inReach.

I understand what you’re saying on electronics, but it would have taken a mountain of waterproof maps to have enough detail for that long of a trip. I still had maps, but they were on my electronics. Even as it was I made it fine relying totally on electronics and experience for navigation. I do always carry a compass. In that flat country, where the lakes change shape as water levels rise and fall, and rivers change their course, a GPS is a great tool.

Michael, I too have found the GPS and Iridium systems to be very dependable.

Was it very cloudy or were there storms?  I’ve had my old Garmin e30x fail to get a good consistent fix during storms and I’d be surprised if an iphone did better.

I didn’t notice any difference with my iPhone concerning weather, Michael K.

I had a similar situation happen while on the SWCP in the UK with my iPhone 6. Basically it plotted my location a good 20km inland from my seaside location no matter what nav app I tried to use and Airplane Mode Off or On. Of course, I only noticed it when I needed it most at a diversion on the path. Fortunately, navigating that trek is pretty straight forward. Once I got to the next village it regained its senses and I had no other issues.

Yes, I had a similar problem recently in the Wind River Range.  The iphone GPS just couldn’t get a lock.  Not app specific. Tried restarting, turning off airplane mode, etc. Nothing worked.

I was hiking with a guy who works for Apple and he had no idea what was wrong.

Three other hikers had iphones of various vintages, and they all worked fine. Got back to civilization and all works fine again.

Stumped.

Appears to be a common problem with iPhone 6 but weird that your GPS starts working from time to time. Phones use Assisted GPS (AGPS); it’s possible that when you’re in “town” the phone finds location using cell towers while in the backcountry the faulty antenna prevents the phone from receiving GPS signal.

More at:

iPhone 6 GPS not working

“Instead, it is the antenna inside of iPhone6 that was malfunctioning. The malfunction probably was made more apparent by the iOS update but the GPS issues were a result of antenna malfunction. I called around 6-7 iPhone repair places and 2 of them said they can replace the antenna for 60 bucks. I believe that the part is called “iPhone6 Logic Board Antenna Flex Cable”. Once replaced my iPhone GPS issues went away and all is back to normal.”

Sounds like it might have been a GPS jamming exercise, certainly if your units work again now.

I sesrched “NOTAM GPS Alaska” and found references to some prior almost state-wide exercises but mostly future NOtices To AirMen.

Alaska gets most of these because, well, done anywhere else, it would effect more civilians.

There are provisions for pilots to declare an emergency through ATC and the jamming to cease within 60 seconds, but I find no remedy for a hiker.

Maube ask a pilot friend to check the NOTAMs in advance next time.

Here’s a map of the maximum effected area in a 2017 jamming exercise using equipment at Eielson AFB and Chena Hot Springs;

The iPhone antenna sounds plausible.

David’s mention of jamming exercises is also plausible. Supposedly, in the area around the Twentynine Plams Marine Base (close to where I live) the military does experiment with the technology.

Another thing is GPS receivers need to fix on 3 or 4 sattlelites. Sattlelites drift out of orbit. When a GPS sattlelites drifts out of orbit the signal is tagged as “unhealthy.” From earth the satellite is manuvered back into orbit, once back on track it takes time to verify the transmissions are accurate before it can be tagged as healthy. Even if this happened to you, perhaps the iPhone rejected that particular signal until it got back to a city where cell signals were again available?

If I depended on an iPhone for navigate I would probably upgrade an iPhone 6 based on Pedestrian’s post.

Most phone mapping locks onto cell service once you are in range, so it makes sense your GPS would work in town.  Maybe you GPS antennae was broken and you didn’t notice it because you were in town initially.  I will usually check mine in town by putting it in airplane mode and then turn on just the GPS.  If it works, I know I am good.

Rick M, for me it was all or nothing, either I got an accurate fix or no fix at all.

RVP that seems to match my experience.

Pedestrian, the antennae is a good thought, but usually there seems to be no issues, until I’ve been beyond WIFI/Cell range for a couple of weeks or so. Of course, correlation is not causation. I suspect the Assisted GPS issue as you suggested is related in some way, though.

David, that’s an excellent thought but my inReach GPS was working, and my iPhone GPS was sometimes not working for days straight.

Nick, those are good ideas. It hasn’t been an issue in the past. If I am truly relying on GPS I will always carry a handheld GPS unit as well.

Ben C, for what it’s worth my iPhone’s GPS normally works fine in airplane mode.

Not trying to be a smartass here but you had three electronic devices and only one functioned reliably as a GPS?

I would carry the inreach, compass and paper map after that experience.

Sean, you are welcome to make your own call, but keep in mind that I was out there for two months and traveled about 1,500 miles. Even in this nearly worse case scenario where two devices turned flaky, (a true 1:1,000 type of fluke) I would still, without hesitation, carry what I had again instead of replacing the GPS and iPhone with map and compass. Even as it was I could STILL navigate effectively, more effectively than if I was navigating with map and compass, and when things were working properly the mapping GPS function was superior to old school navigation every which way. It’s hugely challenging to navigate in enormous flat swamps with a paper map and compass, especially when it’s necessary to follow a meandering course.

For me, as a rule a mapping GPS is vastly superior to a paper map. And if I can handle the exception of GPS glitches, and I did, GPS is the way to go.

But that’s just me.

Buck +10 to your choices!

[edited]

I’ve never had a GPS fail.  When doing a longer trip, I typically take a phone/GPS and map/compass also.  I always find myself using the GPS because it’s so much more efficient and accurate.

I’ve had a similar experience in the Frank Church Wilderness of Idaho. There were several days of a 2 week trip where neither my wife or I could get a GPS location from our iPhone 6s. Tried rebooting, different apps, etc. We didn’t have a backup GPS since we weren’t doing any complex navigation. We had an underpowered GoalZero solar panel/battery and as a result we were charging our phones very small amounts whenever the battery pack had stored enough juice. Even though our phone battery strength read about 50%, I was wondering if the incremental charging and never getting it back to full power did something strange to affect the GPS. Weak theory I know, but had no other explanation.

Once back in civilization, and on subsequent trips, the GPS worked fine.

Curious about the GPS jamming. The Frank Church is close to the Mountain Home Air Force Base and it’s not uncommon to see fighters doing exercises over the wilderness.

@pedestrian

To each their own.  I would never rely on an electronic device.  Others do – we each walk our own walk.

I didn’t realise that it was some kind of competition in here.

[edited]

Let what go?

I stated that if it were me i would use the Inreach map and compass – if i had experienced GPS and phone failure.

i.e. use the most reliable device.

if it were me.  Not if I was someone else.

Don’t get so excited about it.

[edited]

Wow, it sounds as though pedestrian appointed himself the final arbiter here on BPL.

You have no idea about the experience or skills of Sean P yet you are very quick to react and, in my opinion, your tone is very abrasive.

I thought that was a good comment Sean, thanks

I like different comments from different people, a range of possible ideas to consider

Me, I always take one GPS and one paper map.  Out of 100+ trip my GPS failed once – couldn’t even acquire any satellites.  I left it in car and had to reload software from my PC when I got back home.  Occasionally it loses connection, like in a canyon, but I can figure out where I am from the last good location, and it finds satellites again later.  Once it showed me going the wrong way on a trail which was confusing but I just kept going, and after a while it snapped back to the correct location.

I think a paper map is good, but more than that, I keep large features in mind, like ridges and valleys, and how to get back to the trail.  Sometimes, I will go forward enthusiastically, and forget to keep looking backwards.  Then, when I’m furthest out there, I’ll forget where I came from and how to get back.