Airtel 4G doesn't work well on Band 40 on my iPhone 6S (A1688 Verizon Model), works on Band 3


raksrules

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I have iPhone 6S bought from US and its model number is A1688. It was originally Verizon Model which means it was sort of Unlocked (LTE/GSM Part). I have been using the phone on Vodafone and it always worked fine. Even 4G Part (except where network was crappy). When 4G wasn't good, it would fallback to 3G.

I recently ported my number to Airtel as it is supposedly having better network at my home, office and the route between. But with my iPhone 6S, whenever the phone is connected to Band 40, most of the times, the 4G does not work properly. The signal shows as 4G but actual apps / websites etc don't work / open. When connected to Band 3, it works fine. I checked this by entering field test mode in my phone. Whenever, while using the phone, even with strong 4G network, I found that actual stuff doesn't work, I would go into field test mode and see the band. This is how I deduced that Band 40 isn't working properly while 3 does.

Now, for a day, I put the SIM card in my iPhone 5S which is originally Boost Mobile (from US) and it has been unlocked. This is model# A1453 and does not even have Band 40 but does have Band 3. I tried the phone for entire day and the 4G on it was strong at almost all the places and it sort of never failed on me. I reckon, my phone was always connected to Band 3 as it does not have Band 40 anyways.

So what exactly is the problem here and why I am facing deteriorated performance of 4G on my iPhone 6S when connected to Band 40. To top it, I believe Airtel has shut their 3G network so my phone directly goes to NO data mode (not even edge most of the times) as there is no 3G fallback. I don't really intend to buy a new phone as my 6S still works well and I want to avoid using the 5S.
 
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raksrules

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So I went ahead and tried all the below..

1. Reset Network Settings.
2. Reset entire iPhone and restore backup.
3. Restore entire iPhone and setup as New.

Nothing helped me fix this issue so now for next 3 months, I cannot use the 6S until I port back to Vodafone. Using my 5S now and I so much more appreciate my 6S as it feels more like a new phone. Probably gonna keep my 6S longer with this. :)


Just to add, I tried my wife's iPhone X which is also Verizon model and in her phone, Airtel 4G works fine even when connected to Band 40. It appears that I never found this issue in US as always phone was used on Cricket Wireless and then Mint Mobile (T-Mobile) and both don't use Band 40 for LTE.
 

vyral_143

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Referring to above link, I think you have to stick with Vodafone if you are to continue using 6S. Reason being in Mumbai, both Airtel and Jio are using Band 40 - 2300MHz for their operations along with other bands. It appears only Vodafone/Idea does not use it. This link has much more information too.
 

raksrules

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Referring to above link, I think you have to stick with Vodafone if you are to continue using 6S. Reason being in Mumbai, both Airtel and Jio are using Band 40 - 2300MHz for their operations along with other bands. It appears only Vodafone/Idea does not use it. This link has much more information too.
That link has so much overwhelming information and most of it I don't understand.

But then why does the Airtel 4G work fine on Band 40 on my wife's iPhone X (Originally Verizon)? For now, I am using 5S (which I saw switches between Band 1,3,8 for 4G) and then once 3 months of my MNP are up, I will switch back to Vodafone until I plan to get a new iPhone.
 

vyral_143

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But then why does the Airtel 4G work fine on Band 40 on my wife's iPhone X (Originally Verizon)?
Probably Band 40 is locked on your 6S ? I know that GSM part of being unlocked for Verizon phones due to some spectrum deal/transaction. I also used to source such models back then :p
 

raksrules

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Probably Band 40 is locked on your 6S ? I know that GSM part of being unlocked for Verizon phones due to some spectrum deal/transaction. I also used to source such models back then :p
Well, the phone does connect to 4G fine and I can see full network and even 4G symbol but actually, nothing works. Because, at least on my 5S, the Airtel network is great and 4G is also pretty good (no band 40 on 5S) .
Now I am wondering that the issues I had faced with Vodafone of bad reception or dropped 4G at certain stretches of road are indeed network issue or my phone problem. Earlier, only used till 3G so probably never faced issues and when 4G started spreading in India, I wasn't here so effectively, the first time I used 4G in India was in Feb 2019.
 

blr_p

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Referring to above link, I think you have to stick with Vodafone if you are to continue using 6S. Reason being in Mumbai, both Airtel and Jio are using Band 40 - 2300MHz for their operations along with other bands. It appears only Vodafone/Idea does not use it. This link has much more information too.
I find those images very confusing. How did you figure that only Vodafone is using 1800Mhz, is it because maha is shown in yellow so band 3 ?

maha spectrum.jpg
 
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vyral_143

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I find those images very confusing. How did you figure that only Vodafone is using 1800Mhz, is it because maha is shown in yellow so band 3 ?

View attachment 84131
I started from point 1 where they list out circle. Here, they classify circles in 3 categories and metro separately.

Now in point 6, which is for Band 40 - 2300MHz, I see that only for Airtel and Jio, Mumbai has mention of 30MHz whereas Vodafone has no mention.

Further; in point 7 for 2500MHz, I see Vodafone has 20MHz in Mumbai, point 5 for 2100MHz Vodafone has 10MHz spectrum. So overall Vodafone does not have any spectrum in 2300MHz band in Mumbai.

To add, color coding of spectrum bands at beginning and color coding in map is not related.
 

blr_p

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Ah, now i see it, Bombay does not have a mention for Band 40 for Vodafone
 

raksrules

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I confirmed with my brother's Jio sim and same issue on my iPhone 6S. The internet would not work even with full LTE strength and under field test mode it showed I am connected via Band 40.

So yes either I am coming back to vodafone for few more months post April or will continue using 5S and will get new iPhone post launch of iPhone 12.
 

6pack

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Not sure how it will matter but I saw that info on some site which I forgot.