ZE500KL - GPS Issue

[Math43]

Hi,

I've a big problem with my ZenFone GPS, it's very slow to fix and accuracy is very bad. It's totally unusable for car navigation. For example my moto G first gen 2013 have better accuracy (11 meters) and fix in 5s max versus 30/40s with bad accuracy (40meters).

I've try to upgrade to latest firmware, factory reset my phone but problem still here.

I google a little about my problem and I found i'm not alone to have this GPS issues.

Does someone found something to fix this problem ?

 

[vezemkota]

Hi,

I've a big problem with my ZenFone GPS, it's very slow to fix and accuracy is very bad. It's totally unusable for car navigation. For example my moto G first gen 2013 have better accuracy (11 meters) and fix in 5s max versus 30/40s with bad accuracy (40meters).

I've try to upgrade to latest firmware, factory reset my phone but problem still here.

I google a little about my problem and I found i'm not alone to have this GPS issues.

Does someone found something to fix this problem ?

You're not the only one with this problem, bro. I also have a problem with GPS on my ZE500KL (by the way, i also had Moto G 2013 before and GPS works good on it)

AndroiTS GPS Test shows that GPS doesn't see any sattelites. The best result was connection with 2 sattelites, and the accuracy of GPS on Google Maps was very low in anyway.

I have tried factory reset, to downgrade to WW_12.8.5.118 Firmware & wipe cache partition, then tried also install WW_12.8.5.172 and WW_12.8.5.222 firmware and the result is the same - GPS not working.
The only thing I didn't tried yet is editing the "gps.conf" file, but I need root for this, and I don't want to lose the warranty

As I see on ASUS official forum, they know about the issue and they trying to resolve the problem (since november or something). :good:

 

[AntonZem]

Same for me

Gps position updates once a minute and accuracy is real ****. Had a road accident because of navigation problems

 

[danielr]

same problem for me...good phone, but GPS work badly

 

[venomus001]

gps on my ze550kl keeps turning around and accuracy is very bad hope they will fix that in MM

 

[BubuXP]

I tried to post this message on the Asus Zentalk forum, but the site seems broken, it won't let me post anything.

I had a similar problem with my Moto G, I resolved this way (solution found in this forum, posted back to CM forum):

To make integrated GPS working you need to reboot in bootloader mode (hold volume down while turning on the phone), then attach the phone to the pc with the USB cable, and from the command prompt use fastboot to erase modemst1 and 2:

fastboot erase modemst1
fastboot erase modemst2

It will not erase anything tangible for the user (apparently).

I know that this is a different phone (I should get it soon btw, I hope I will not regret my choice) and that the commands probably won't work even with some modification, but it could give a hint to those trying to solve this problem.

 

[rozene05]

I tried to post this message on the Asus Zentalk forum, but the site seems broken, it won't let me post anything.

I had a similar problem with my Moto G, I resolved this way (solution found in this forum, posted back to CM forum):



I know that this is a different phone (I should get it soon btw, I hope I will not regret my choice) and that the commands probably won't work even with some modification, but it could give a hint to those trying to solve this problem.

i tried the code but her is what happened... see screenshot
postimg.org/image/jxx5n1sxl

hoping for a response...

 

[BubuXP]

i tried the code but her is what happened... see screenshot
postimg.org/image/jxx5n1sxl

hoping for a response...

Have you run the command prompt as Administrator?
Have you installed the latest or official ADB drivers?
Have you unlocked the bootloader? (I don't know if necessary, try the above first)

 

[rozene05]

I also tried running as admin as well as downloaded the latest adb and drivers, same result

I have not yet unlocked my bootloader since there is no complete backup here at xda, and it is not possible to re lock the bootloader,

I will just be waiting if someone will try to it.

 

[BubuXP]

I also tried running as admin as well as downloaded the latest adb and drivers, same result

I have not yet unlocked my bootloader since there is no complete backup here at xda, and it is not possible to re lock the bootloader,

I will just be waiting if someone will try to it.

I'm investigating what happens in detail when these two partitions are erased.
I found two discussions that look interesting (specially the second):
http://forum.xda-developers.com/zenfone2/general/investigation-efs-t3153154
http://forum.xda-developers.com/showthread.php?t=2617276

In brief: these two partitions holds important information of the phone, like the IMEI. Erasing them cause the system to recreate them using the information backed-up in other partitions. But in some cases these backup partitions are empty and erasing the modemst partitions cause the phone radio to stop working (no more calls, 2G/3G/4G data and GPS) because the system cannot retrieve the serial numbers needed to make the radio work anywhere.
So it's better to do a manual backup of these partitions before erasing them (better a full backup with TWRP, that will backup all partitions including these).

Reading the second discussion linked above suggests me that the sudden bootloop problems that people are experiencing, are also connected to the corruption of these modemst partitions (corruption possibly caused by some firmware update or by some system app gone mad).


The fact that Asus after 2+ months still hasn't fixed the GPS problem, could mean IMO:
- that the problem isn't related to the above partitions and is more complicated than it seems (probable);
- that the problem is caused by the corruption of the partitions but it cannot be fixed with an OTA firmware update, but only manually with a technical intervention (full flash and/or terminal bashing) that regular users aren't capable of;
- that the problem can be fixed with a firmware update but Asus developers still haven't find that (improbable).


I should get the ZE500KL in a couple of days, then my theory could be tested directly and described in detail (if I get the same GPS problems after updates).

 

[rozene05]

Thanks for your input regarding this, i would just use my bluetooth gps in order to navigate properly..

 

[BubuXP]

Thanks for your input regarding this, i would just use my bluetooth gps in order to navigate properly..

Yesterday I received the phone, I booted it to check if it works, then I immediately upgraded the firmware to the latest version, without OTA updates but downloading directly the latest full firmware from the Asus download site.
Then I booted the phone, played a little with it, did a full reset and re-flash the firmware.
Then I thought about GPS problems and I tested it with AndoiTS GPS Test and it seems to work fine, or at least I suppose this from the attached screenshot (I couldn't test it on the streets yet).

I don't have root permission or bootloader unlocked [yet], so you and everybody could try the same things I did:
- Factory data reset (from Settings > Backup and reset menu);
- wipe data/factory reset (boot into recovery by pressing Volume Down button while turning on the phone);
- full firmware flash (from recovery, you can copy the firmware zip file in a microSD or upload it via adb sideload).
Then after rebooting the phone complete the welcome procedure and repeat the three steps above another time.
I hope this will works for everybody.

 

[rozene05]

Here is my screen shot using asus zenfone 2

 

[rozene05]

Screenshot from asus zenfone 2 ze500kl
Merely 2 satellites

And here is the screenshot using xperia sp c5303,


I also updated using the zip in asus site and flashed it,
Btw, my asus has been rooted, but i see no difference after rooting it, same scenario 2 or less satellites, some times 5 but no fix

 

[rozene05]

Yesterday I received the phone, I booted it to check if it works, then I immediately upgraded the firmware to the latest version, without OTA updates but downloading directly the latest full firmware from the Asus download site.
Then I booted the phone, played a little with it, did a full reset and re-flash the firmware.
Then I thought about GPS problems and I tested it with AndoiTS GPS Test and it seems to work fine, or at least I suppose this from the attached screenshot (I couldn't test it on the streets yet).

I don't have root permission or bootloader unlocked [yet], so you and everybody could try the same things I did:
- Factory data reset (from Settings > Backup and reset menu);
- wipe data/factory reset (boot into recovery by pressing Volume Down button while turning on the phone);
- full firmware flash (from recovery, you can copy the firmware zip file in a microSD or upload it via adb sideload).
Then after rebooting the phone complete the welcome procedure and repeat the three steps above another time.
I hope this will works for everybody.

Another question what firmware version are you using, as far as my experience, the latest ww.12.8.5.222 firmware gives me this problem so i decided to do a full downgrade to the stock fw that comes with my phone, which is ww.12.8.5.118, for that fw works before

 

[BubuXP]

Another question what firmware version are you using, as far as my experience, the latest ww.12.8.5.222 firmware gives me this problem so i decided to do a full downgrade to the stock fw that comes with my phone, which is ww.12.8.5.118, for that fw works before

I used the latest firmware, the .222
The trick could be resetting and flashing, two times, but it's only an assumption.

BTW, into geolocation settings, I enabled the only GPS option when doing the test.
In your screenshot, it looks like AGPS is enabled, that is not GPS. Try setting only GPS in the geolocation settings and see what happens (maybe with screenshot).

 

[rozene05]

Here it is without agps, i even left my phone in the open for about an hour, screen on, hoping it will fix even with one satellite, now even one satellite wont show up

 

[BubuXP]

Here it is without agps, i even left my phone in the open for about an hour, screen on, hoping it will fix even with one satellite, now even one satellite wont show upView attachment 3688327

Ok, it looks like the same exact problem as the Moto G, and the solution should be the same too.
But with the bootloader locked (and no way to unlock it at the moment), the only thing we can do is using the terminal with root privileges to backup and erase the partitions (with the dd command or something similar).
I'll study how to do this...

 

[rozene05]

Just to update

 

[4llerbuntu]

Just to update
View attachment 3689322

so what did you do to solve it?