[HowTo] Fix GPS issues (and SIM)

Apr 3, 2017
7
3
3
#21
I've been running some tests last weekend and this is what I found.

With stock 1.9.063 (Z2131_CN_OPEN_USER_Q01002.1_M_ZUI_1.9.063_ST_160604_qpst) and baseband 9-00009-M8996FAAAANAZM-1.53476.1 I was able to get a maximum accuracy of 3m.

With stock 2.0.069 (Z2131_CN_OPEN_USER_Q01017.1_M_ZUI_2.0.069_ST_160712_qpst) and baseband .2.0.c1.9-00026-M8996FAAAANAZM-1 the best accuracy was 6m.

The last attempt with ZUI 2.3.042 (zuk_z2_Z2131_ZUI_2.3.042_ST_161013_QPST) and baseband 9-00026-M8996FAAAANAZM-1.63821.1
was around 4-6m.

So the best result was with the oldest baseband. I used the app GPS Status and the lock only took a few seconds.

After that I unlocked the bootloader, flashed the recovery twrp-3.1.0-3-z2_plus and clean installed and rooted LOS 20170420 with magisk. I cannot get a GPS fix anymore (baseband 9-00026-M8996FAAAANAZM-1.63821.1).

If I install TopNTP as suggested in other posts, I can get fix in a few seconds but the accuracy is not as good as with stock ZUI. It's around 15-20m.

Hope this can help.
 

gapo

Active Member
Jan 31, 2017
111
42
28
#22
I've been running some tests last weekend and this is what I found.

With stock 1.9.063 (Z2131_CN_OPEN_USER_Q01002.1_M_ZUI_1.9.063_ST_160604_qpst) and baseband 9-00009-M8996FAAAANAZM-1.53476.1 I was able to get a maximum accuracy of 3m.

With stock 2.0.069 (Z2131_CN_OPEN_USER_Q01017.1_M_ZUI_2.0.069_ST_160712_qpst) and baseband .2.0.c1.9-00026-M8996FAAAANAZM-1 the best accuracy was 6m.

The last attempt with ZUI 2.3.042 (zuk_z2_Z2131_ZUI_2.3.042_ST_161013_QPST) and baseband 9-00026-M8996FAAAANAZM-1.63821.1
was around 4-6m.

So the best result was with the oldest baseband. I used the app GPS Status and the lock only took a few seconds.

After that I unlocked the bootloader, flashed the recovery twrp-3.1.0-3-z2_plus and clean installed and rooted LOS 20170420 with magisk. I cannot get a GPS fix anymore (baseband 9-00026-M8996FAAAANAZM-1.63821.1).

If I install TopNTP as suggested in other posts, I can get fix in a few seconds but the accuracy is not as good as with stock ZUI. It's around 15-20m.

Hope this can help.
I'm using LOS 20170420 with Magisk also and GPS works fine. I installed custom ROMs after flashing ZUI 1.9 and then ZUI 2.5
 
Apr 3, 2017
7
3
3
#23
I'm using LOS 20170420 with Magisk also and GPS works fine. I installed custom ROMs after flashing ZUI 1.9 and then ZUI 2.5
I've flashed ZUI 2.5, locked the GPS and then flashed LOS 20170420 again and the GPS worked fine.
Then I used the 'reset' option of the GPS Status app and it doesn't get a fix anymore. So I guess that confirms the issues with the initialization.

Setting the 'Sensor filtering' to no filtering in the app makes the gps to get a fix but the accuracy is terrible, around 30m.

I'm also flashing the stock package of gapps excluding google+ and google camera. Could the gapps distribution/package make any difference with the gps behavior?
 

gapo

Active Member
Jan 31, 2017
111
42
28
#25
I've flashed ZUI 2.5, locked the GPS and then flashed LOS 20170420 again and the GPS worked fine.
Then I used the 'reset' option of the GPS Status app and it doesn't get a fix anymore. So I guess that confirms the issues with the initialization.

Setting the 'Sensor filtering' to no filtering in the app makes the gps to get a fix but the accuracy is terrible, around 30m.

I'm also flashing the stock package of gapps excluding google+ and google camera. Could the gapps distribution/package make any difference with the gps behavior?
I use Pico gapps right now. But I've also installed ROMs using nano and stock and never had any problem.
 
Feb 11, 2017
47
33
18
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#27
I started running again and this drove me loopy. QFIL is a pain for me since I don't own a PC, so decided to try DarkMoon again. Had issues with this kernel in the past regarding battery life but for this issue, it seems to be good. I get a lock in under 30 seconds and accuracy settles between 5-10 metres.
 
Dec 11, 2017
3
0
1
#28
Thank you so so so very much for this thread.
I have been hitting my head hard for so many days for trying out the latest Oreo baseband but it totally messed up my GPS and showed me in Tokyo.
Finally getting to this post I flashed the deodexed stock rom to get a gps fix and I am rescued...actua act my phone is rescued but so am I.
Only thanks to awesome people like you guys.
Thank you so much.