Network type falling back to WCDMA/GSM

[Delph1]

Hello,

got a Z1C a week ago. I never get 4G/LTE signal. My carrier is ok, cause if i put my sim in a LG G2 i get 4G/LTE.

From Network settings menu, if Iset network type to LTE/WCDMA/GSM, after a while it catches 3G/H/H+. Going back in the menu, the network type falls back to WCDMA/GSM.

From *#*#4636#*#* menu, if I set mode to LTE-only, I don't even get signal.

Is updated to last version (android & apps)

baseband 8974-AAAAANAZQ-10270075-68
Build 14.5.A.0.270

Help !

[Uliwooly]

@Delph

is your Z1 compact compatible with your network's LTE bands? do you have the correct APN settings? are you using a nano SIM card? 

[Delph1]

uliwooly

Thanks for your answer.

1) carrier band is 7 (2600MHz) only atm. Should be OK

2) APN settings : tested APN settings sent at first start from carrier and ones downloaded from sony by network menu. Difference is minimal (sony adds a-gps and dial up flags but carrier replaces hostname on mms apn by IP). Both allows me to 2G/3G/H/H+ and send receive mms

3) Sim card is an old (4years) 2 format sim. micro and normal with adaptator.

Regarding APN settings, do you have some particular settings for LTE ? I saw the LTE flag in Network APN setting.

[briant566]

 This is exactly my problem mine seems unable to lock on to  weak signal it has been sent back 3 time but all they say is it is within spec ,Which i agree but only if you are in a full signal are

Mine has only started since updated to lollipop 

So it seems  to me that the 4 g signal has been used and the 3 g lowered

My post is weak  "network signal "

[Delph1]

briant566

I have no weak signal problem. My 3G signal is like my LG G2 signal.

Our problems are differents in my opinion

[briant566]

 sorry yes you are right having read your post again

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@Delph wrote:

@briant566

I have no weak signal problem. My 3G signal is like my LG G2 signal.

Our problems are differents in my opinion

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[Uliwooly · Accepted solution]

@briant566

What I would do is to get a brand new MICRO SIM card, even if the old SIM card works. 

[Delph1]

@uliwooly

I did some tests showing that this is a very WEAK signal problem. I can get LTE if i stand near the antena.

On my LG G2 if I have less than 3 bars out of 5, the I can't get LTE on Z1C.

This is very anoying.

[Uliwooly]

@Delph

Don't rely on the bars, check 

settings > about phone > status > signal strength on both phones. 

[Delph1]

Since yesterday its fixed. Don't ask me how... Staying to lte prefered and getting lte. Last thing i did was forcing carrier network to lte after a manual search.

Uliwooly: you were right. Got only 3 db difference.