GPS issues since update

[#1]

Hello Sony and other users

If updated my Neo last week from the stock firmware to 2.3.3 build 4.0.A.2.368.

After that I have issues with GPS signal (DOP). Programs like RunGPS, Google Maps and Navigon loses GPS signal exactly every 5 minutes für about 30 seconds. After that, the DOP is good again. Sometimes it helps to restart the phone, sometimes not. I've tried to find out if it depends, which programs are in the memory but nothing is really obvious.

The issue looks like this:

Yesterday I've updated to 2.3.4  4.0.2.A.0.42, but the issue is the same. I've read in another forum that sometimes an update of Googe maps could cause this problem. So I've deinstalled the last update of Goggle maps. Before that I had this issue, directly after that it was gone, but it came back although I did not install the update of googe maps again (Auto update was disabled).

Before the firmware updates I did not have this issues.

What can I do? Are there some log files, which can help? Any idea?

With this issue the GPS is not really usable. Is it possible to downgrade?

Thanks

[maRRRco]

My is an original no brand

I also tried a software repair but it doesn't work

something try to collect data even if it shouldn't !!!

[ROB_GAS]

Then I supose mine will fail again, I'll Let you know

[maRRRco]

Now a test at home

first of all i cleared Maps cache and data, but this don't work like i supposed, a software can't affect gps running

then i try to run gps with connection, in my case wifi

so i turn on the router, activate wifi and the same in the phone

start Sygic navigation, and no dropouts after 5 minutes, very good

(in this case i didn't set "use wireless network", but i turn on the real wifi radio)

what does it mean?

simple, with connection the agps find data and refresh the status of satellites with nice precisione

so who have a data plan in his phone don't find the problem

what is wrong?

simple again, during his work, gps must not search for data, so if you have connection or not, after first fix all must running nice without drops trying to search data

in our case who have connection ON don't find the issue but it is still here

who don't have connection, find the problem after every 5 minutes

if is really so, the problem of JoyoNeo is a little different, because he has connection

perhaps in his case is really a provider problem or something else

but without connection his problem is identical to my and other and must to be fixed

I repeat again, with firmware 3.0.xx.145 this didn't happened

[#5]

Hi you All

And now totally strange.

error - no error - and arror again. Thats new. Everything with data connection on:

I'm done now with tests and protocols.

Sony, its your turn.

Bye

[maRRRco]

Hi Joyo

I think your tests are a little difference from our

you say that the problem start after 2 hour or so from the first phone boot

while in my and other cases the problem happen immediatly

so sometimes your gps works well, could be a provider issue ?

perhaps your Sim loses the comunication to servers and this cause a dropouts when the gps required data

this is a possible explanation, however in all cases, with no data it MUST work well

this is the only real thing, a normal gps after the first fix don't need more data, so is a bug, even the people who it works well, have this bug, but a stable connection hide it !!!!

Sony please does something fast, is so difficult get the configuration of the build 3.0.xx.145 and put it in a new firmare, or better say us what to do to solve this before a future software ?

[Oskar-GPS]

Hi All,

First of all I want to thank you all for the information that we've received. Right now I think that we have all the information that we need to solve the problem.

I'll try to explain more about what is causing this so that you can find ways of avoiding it while wating for it to be fully solved.

There are certain information that the GPS receiver needs to function optimally:

     1. GPS time (which is known if you have a GPS fix)

     2. Rough location estimate (which is known if you have a GPS fix)

     3. Detailed information about satellite orbits called Ephemeris (which is decoded from each satellite above the horizon and takes about 30 seconds per satellite)

     4. Rough information about satellite orbits called Almanac (which only needs to be decoded from one satellite and takes about 12 minutes)

To get this information quicker than decoding if from the satellites we try to download it from a server over the Internet.

Every 5 minutes the GPS receiver checks if any information is missing. Even if you have a GPS fix the almanac might be missing and a connection attempt will be triggered.

So what you should do is to make sure that you already have all the info that the GPS receiver might need.

One way of doing so is to let the GPS receiver run for about 20 minutes in good signal conditions to decode the Ephemeris and Almanac from the satellites.

An other way of doing it is to download the data from the server while on WiFi connection. When the data downloaded from the server becomes stale you will need to decode it from the satellites or update it over a WiFi connection or you will start loosing the GPS fix again.

To force the data to be downloaded you should install an application that calls the LocationManager.sendExtraCommand("gps", "force_xtra_injection", null) method while on a WiFi network.

//Oskar

[maRRRco]

Really i don't understand well, or better, ok for the infos about a normal gps works.

But still don't uderstand why try to get these basic informations from the server, when usually the process is the same quicker.

En fact in flight mode we have no signal dropout, that mean these infos are not necessary.

Then even if we try to collect these infos like you say, or waiting 20 minutes, or using a wifi connection, the signal drops the same after this or after a day, so the gps is unusable, the tests show this clearly.

Then you say that we can find a method to avoid the problem, but you mean waiting 20 minutes or using wifi connection?

This not work :smileysad:.

Regarding to force data, I don't understand how it works, you speak about downloading an application, but that is a command line

Not would be more simple at the moment, waiting the problem fully solved, try a method to avoid these connections and leave the gps work like does an old tomtom or a normal navigator without data?

Something change from build 3.0xxx to 4.0.2.A.042, why before worked and now not?

Even if the basic infos that gps required are the same, why before software didn't required that and now yes ??

this is the point

[ROB_GAS]

NOT working againg this morning, i hope Oskar find us a Solution

[ROB_GAS]

As MaRRRco says once yo have a GPS lock it shouldn't drop it to look for a data it already has. I think we all have tried to clear AGPS data with "gps status" or "gps Test" or even trough the service menu and nothing seems to work always.

I expect that sony can upgrade the software to solve this and it would be great if you could provide a workaround or a method to make it work even using third party applications.

I think we all would be very grateful

[#11]

Hello Sony and other users

I am an owner of an Xperia arc from November 2011 updated to 2.3.4

I found the same problem to other users, frequent disconnections (after 5 minutes) of the GPS signal, I tried several navigation software and the problem remains with all, I tried software for fixing satellites but nothing has changed.

Best regards