Problem with 5GHz Wifi on iPhone 12 Pro

I had the same issue from purchase with the iPhone 12 Pro Max, checked IP, hub and DNS with no fix, took it back to apple and showed proof of where mine has issues connecting to the 5Ghz signal but, was working fine on 2.4Ghz unless AirPods Pro was connected and in use, then neither would work. The iPad Pro, and another iPhone XS Max were all working fine as normal.

Once I got the new iPhone everything was working fine until a backup and restore caused the issues to start again, from this I forgot the networks before backing up and restoring again, since then had been working fine,

Updated to 14.3 over the air and issues restarted, so I do have a feeling it’s software related more than hardware.

For what it's worth - I had a similar problem - weird that Safari was working but others like youtube and the stocks app weren't connected. For me the culprit was my VPN software/app. For some reason, my VPN was switching on/off repeated (and quickly) -something wasn't playing nice. I disabled the VPN connection, and voila - connectivity again. I haven't dug further into the solution on the VPN side, but I will.

My iPhone 12 had the same problem. Speed test over 5GHz WiFi was as slow as 0.6Mbps download, while over 2.4GHz it is around 15Mbps.

Here is what I found after a bunch of troubleshooting.

On my Netgear WiFi router I had single SSID for both 5GHz channels. So I splitted them up and assigned the two 5GHz channels with different SSID, for example 5G-1 and 5G-2. Connect the iPhone to either of new SSID and see the Speed test is much better. Now I'm getting up to 200Mbps download speed which is pretty much my service plan. Occasionally the speed over the lower channel (36 ~48) drops down to 150Mbps, the higher channel(149~161) has been constantly giving over 200Mbps.

Hope this helps.

Had a similar issue on my iPhone XS Max.

The problem:

- wifi 5 GHz was too slow ( < 1Mb) or even was not working (in most cases);

Note:

- at the same time wifi 5 GHz perfectly is working on iPad and Pixel 2 XL;

- wifi 2.4 GHz is working with no issues.

What was discovered:

- wifi 5 GHz was not working on iPhone when it is in the room with the router (i.e. the distance between devices is too low, no walls). When I tried wifi in the other room (~5-7m from the router + 2 walls) it started working! Without any issues!

Fix in my case:

- I have D-Link DIR-853 router. Disabling DFS option (on wifi 5 GHz settings tab) resolved the issue and it started working in the same room with the router on full speed!

That is frequently caused by an IP address conflict. Try restarting your router. You should also turn off Private Address for your home network; it is a feature that protects you on public networks, you don’t need it on your home network.

Hello everyone,

After trying everything, it is simply sorted out for me by resetting the router. I used to split the 2G network from the 5G one by having different SSIDs, but when I have them merged as one it is just sorted. Splitting the 2G from the 5G bands was always a great thing to have quicker WiFi connection, but this solution worked out for me. I hope this is helpful for you guys as well and good luck.

I have the exact same problem you and others describe.

On my 5ghz Wifi at home I have trouble with some services with my brand new iPhone 12. I'm on latest iOS 14.3 I can connect to the wifi and most services works fine and stable with max speed: for example browsing, facebook, youtube, mail, spotify, speedtest.net etc.

However the following services just hangs and loads forever (or until a timeout error):

• Backup iPhone to iCloud
• Streaming movies/series from Apple TV+, Netflix, Viaplay, and all other tv streaming apps i have tried.
• Apple Music

If I use an iPhone 8+, XR or 11 also on iOS 14.3 everything works fine on the same network.

If I switch my iPhone 12 to the 2.4ghz network on the same router everything works fine

If I connect to my range extenders 5ghz wifi (cabled access point with different SSID as the main 5GhZ wifi) everything works fine.

If I go to another house and connect to another 5ghz network from the same ISP but they have their ISP provided fiber modem/router in bridge mode and use the Netgear Orbi RBK23 Mesh router, everything works fine.

I have tried all suggested solutions in this thread with no luck. In two occasions I have gotten streaming music and movies to work (but not iCloud backup) by turning off and on "Private Network" for the 5ghz network. It don't last. If I connect to another network, and then back it stops working again.

I have spoken to apple support (senior dept.), but no solution. My case should be escalated in the system by them, and I have reported it myself as well. If everybody experiencing this problem reports the problem here: https://www.apple.com/feedback/iphone.html, we might in the end get focus form apple.

I have also reported the issue to my ISP (Altibox Norway) who has provided my Wifi Router (FMG home central). They where aware of the issues for streaming apps, but not that it affected backups to iCloud. They said they where working on it. I got a new beta firmware update, but it did not solve the problems. Hopefully they find a solution for me and their customers.

In the end I think Apple need to fix something for all their affected iPhone 12 customers. They can't expect us all to buy new routers/ap's when the existing works well for all other devices...

Have anyone else found a reason for this problem or even better a solution?

I am looking for a solution to the problem in the original post in this thread: "some apps/services are not working on 5ghz wifi."

I am not looking for a solution on unstable/slow networks.

@RODAR21 made my day.

This helped. I have had the same problems on my IPhone 12Pro as the author of this tread. I disabled Wifi Assist in «settings-> cellular. Now I can use my phone with my home central which has wifi 5ghz and tv signals in the same box. (No external wifi router). Thanks a lot. Hope this will solved this issue permanently.

It's not an issue with the hardware in your phones but may be with the firmware in your router.

This is my 12 Pro Max on a Ubiquiti router on a 802.11ac 5 GHz network:

Make sure you have Wi-Fi Assist shut off, as if your Wi-Fi connection is noisy, your phone may be using cellular data to supplement the transfer.

About Wi-Fi Assist - Apple Support

I encountered the same issue where several apps hang and doesn’t load. It recovered when I turn off private address in IOS14.

Make sure that your phone is updated to iOS 14.3. If it is a new phone it probably isn’t. Go to Settings/General/Software Update.

FrostbiteXX Said:

"Problem with 5GHz Wifi on iPhone 12 Pro: Thank you for your reply and your thoughts, but unfortunately this can’t be the problem because as soon as I switch to my 2,4Ghz WiFi ‘everything’ works just fine. I don’t have any of the above mentioned problems with the 2,4Ghz WiFi, just the 5Ghz. But, as mentioned it is ONLY the new 12 Pro. All other devices in my house work fine with the 5Ghz WiFi.”

———-

Get this Serviced:

• The Modem nor the Router is the Issue:

It is likely not an error with the Router/Modem. All other items can access the 5GHz broadcast frequency.

• Perhaps this is a Faulty Device?

If Wi-Fi is having issues, then something is misconfigured. You have a one-year, out-of-the-box, limited warranty. So, contact Apple Support, and have this looked at.

• Apple Contact Us Info:

--- Contact Us - Choose Locations

--- USA: 1(800)MY-APPLE

--- Proceed from there as Necessary

• Why the Wait:

It may take a few just to get through to Apple Support. And that makes sense because many are working out of their house and taking classes from home, this having my time on their hands to contact Apple Support. So, just stay on the line, and you will most certainly get through.

Guys try overriding DHCP to set manual address,mask and gateway. Also replace DNS details with google’s (8.8.8.8 & 8.8.4.4). This has worked consistently for me to fix bad performance on 5GHz and sometimes failures on 2.4GHz. Once I set it manually like this the phone behaves as my iPhone 8 did indefinitely. So it’s good news that it’s not a HW issue. Can others try this please?

If manually setting a DNS server solves your issue that means the default DHCP server assigned by the router is suspect.

For most people a router will route the DNS service for DHCP clients through your ISP's nameserver (e.g for most cable Internet providers) rather than Google.

If your ISP's name servers are being slow, that will be the same for everyone with the same ISP, so manually selecting a DNS server will fix the issue.

It was true for many years that DNS service was the most overlooked part of many IS{Ps' service offerings simply because there was no impetus for them to spend more as people compare on transfer speed, not DNS speed.

Regardless, in most circumstances there's no downside to obtaining DNS services through Google.