Z3 Compact dropping cellular connection

[CB24]

Bought a new Xperia Z3 Compact last Friday, and have run into a problem that I have never experienced before with any of my previous smartphones.
I commute to and from work by train, at one small spot along the route there are one cellular blind spot.
The mobile loses cellular contact for 20 to 30 seconds every time the train passes the blind spot, and then the signal is back. But that’s not the case with the Z3 Compact. After cellular signal is lost, it’s lost forever. Even several hours later the phone has no signal, just a red x over the signal strength bars. If I reboot the phone, the signal is back and the phone is working again.
So, I have to reboot my phone twice every day… Every morning and afternoon.
This is a brand new phone and I am pretty disappointed in the product because of this.
The good old HTC One smartphone works like a charm with the same SIM card.

[Sirocco14]

I have the same exact problem as CB24. I have done just about everything to fix this issue but it's just futile. Sadly, the recent firmware update did not change anything.

Sony, I hope you can fix this issue please. This is my fifth Xperia phone but this is the first time I've had any type of problem.

[charlie3601]

Has anyone got to the bottom of this yet - I have come from a trusty HTC one to a Z3 (non compact, but came across this thread after a search) and find it very irritating to have to keep re-booting the phone when it looses it's/LTE or 3G data signal - for clarity I'm not using stamina mode either - what to do other than give up and go back to HTC? Any advice greatfully received.

[gingerweb]

Yep same problem here on z3 - driving to work is best example when I lose connection 3g doesn't come back until I reboot, then its fine.
My iPhone 4s used to lose 3g for 30/seconds of a 30min drive - my xperia z3 has 3g for about 30 seconds of the drive.
I was hoping this was a fault of my phone but looks like its common

[gingerweb]

Update - I went to the network provider shop and did a "sim swap" and ever since then the signal has stayed strong and on the drive home when it dropped out at the usual place it immediately came back when i went back up the hill - i dont think it has ever done that before, so maybe my sim was faulty ?

wortha  try as its a free solution ?

[charlie3601]

Having contacted Sony support on this they requested I do a repair, which made no difference so I too went for a SIM card change (netowrk is 3 UK) and thus far it seems to have worked, tough wood, but it's only been a few hours!

[charlie3601]

After a day of seemingly being fine following the SIM card change my Z3 has reverted to needing a reboot everytime it drops he data network - very irritating as I quite like the phone otherwise, but I think I'm going back to HTC now.

[Noir]

My problem is almost like the others. I work in a kitchen and as soon as I put my phone, z3 compact, on a stainless steel table top my cellular connection is gone. When I lift it up again my connection comes back, but only sometimes. I have tried all the above tips, though non of them really worked.

[gavmess]

Me too. I'll look down a few times a day and see the red cross over the network and no signal at all. But I turn on and off airplane mode and it jumps back up to full signal.

Does Sony actually read these posts and start their diagnosis or offer feedback/support?

[Barisyaman]

Same problem with my Z3 compact. When  I switch off the phone by power button I lost connection. After I switch on signal come back again in 30 sec. It happens 4-5 timesn in a day. I tried almost everything that you wrote above but results were same. I hate sony z series...Also no one has been given any feed back from Sony or figure this problem out.  Now I am thinking to give it someone as free. Annoying!