解答一些小問題.
還有at&t的論壇也去了一陣子.
只要是工作, 電話打進來就是那麼讓人警張.
反而做起來很開心.
之後4S的wifi就壞掉, 就會變得無法開啟.
換一台不是新的,但功能上可用的,要附$199(特價喔).
有買保固的二話不說, 換另一台給你.
沒保固的, 花美金$199, 也換一台給你.
沒保固也不肯出$199的, 抱歉不受理.
這讓好多人非常生氣.
或 "iPhone wifi" 就可以看到好多人討論這問題.
插入SIM卡就能當GSM用.
查看自己國家通訊服務業者使用的LTE頻率.
去買了𤗿全額付清的 Sprint iPhone5S.
就變成三不管.
蘋果說只有 Sprint 才能解開鎖.
Sprint 說你要先使用40天之後才可解鎖.
所以也無法解鎖.
好倒楣的買者.
因為AppleCare不理賠購買地以外的維修.
LTE好像還要等到 2014年.
LTE, 用過就很難回去了.
Hi everyone, I've gone through more than a few discussion threads discussing wifi issues, and the most frustrating one is the "wifi grayed out" problem.
Here's what I've read:
1.) iPhone4S upgrade to (iOS6, iOS7 and their patches), wifi button gets disabled.
Especially when it happens right after a new iOS upgrade. Other wifi not working problems will not be discussed here.
In the following paragraphs, I've compiled a string of work arounds pulled from the web, in escalation sequence.
A. Software problem?
====================
1. Baseline technique: http://support.apple.com/kb/TS1559
Settings > General > Reset > Reset Network Settings
2. Doesn't fix it? Drain battery completely, plug in power, wifi can be enabled
for some situations.
http://youtu.be/o_ws5srnVVM
This method is easier to do compared to taking the battery out.
3. Wifi still grayed out? Try the freezer technique.
http://youtu.be/5phuLEPUm9o
Maybe the battery didn't get completely drained so as to to clear out wifi settings stuck in limbo state. I'm curious about how the freezer technique works at all. From Apple's 4S tech specs:
Environmental requirements of 4S:
Operating temperature: 32° to 95° F (0° to 35° C)
Nonoperating temperature: -4° to 113° F (-20° to 45° C)
Relative humidity: 5% to 95% noncondensing
I guess the freezer technique works for some situations because it cause the iphone to go out of operational state (not quite same coldness as nonoperational state of -4°F. So when the iphone starts up, it has a better chance of starting from completely fresh. The previous battery drain technique depended on how close to complete drainage achieved.
Up to this point, the 3 techniques of reset network settings, battery drain, freezer, are attempts at doing power cycling on a device that has a non-user friendly removeable battery.
If it were my iPhone4S, and it is out of warranty, and if I don't plan on paying Apple to fix it, I would look at:
http://www.ifixit.com/Guide/Replacing+iPhone+4S+Battery/7111/1
On the subject of why a perfectly good, working 4S, with operational wifi, would suddenly go bad after the iOS7 upgrade?
This type of problem, defined as hardware capable of working operationally but fail during startup. That is why before we perform a major upgrade, a health check needs to be done. In the case of the iOS7 upgrade, I read about a tip that it needs 3GB of storage space.
So I removed a couple of those 1GB+ games, exited out of all apps, then reset my network settings, making sure that it can come up after a reset on the old software. Then I powered it down and started it again. On my PC I reset it to get it into a clean initial state prior to firing up iTunes.
These were done because I've seen instances where you install software on a cpu driven circuit pack, reboot, and it just dies during bootup. Then when we fill out circuit pack replacement reports, the one question asked would be: was it capable of rebooting *and* operating normally on the old software?
Software upgrades tend to be scripted, and those scripts have assumptions about finding files and folders in certain places, and above all, scripts assume there's enough disk space.
This why http://support.apple.com/kb/TS1559 tells us to do software restore from iTunes. The wifi hardware drivers didn't get installed correctly, or it didn't initialize properly for some reason. And iOS doesn't let you go in and install just the wifi drivers, we'll have to restore the whole iOS image.
As a user of Windows for many years, seeing network adapter drivers not starting up is an expected behavior, and I deal with it from time to time. It's just harder to do on the iphone because we can't re-install the wifi driver by itself, and we can't pull the battery easily.
Ok, up to here we were in software territory. Now, let's escalate one notch.
B. Connector problem?
=====================
The 4S wifi circuitry is connected to the antenna by a cable, a very small connector, and this connector is soldered onto the main circuit board.
Could the solder point be compromised through heat generated by use, hard knocks? It's possible. Please see this Youtube video from Leon Stacy:
http://youtu.be/Bg4ZFNnO8vc
If the connector point is loosened or solder points beneath it is cracked, then this may explain why the hair dryer trick works for some people. The dyrer heat expanded the wifi antenna connector and/or the solder points beneath it.
C. Wifi chip damaged?
=====================
The upgrade to iOS7 may have needed (I have no way of knowing, Apple support might know) to update somethings on the Wifi chip itself.
For whatever reason, the wifi chip itself is not working normally after the upgrade, and it would need to be replaced.
Just an example from an iphone repair shop based in Greece. (Disclaimer, I have no relations with them, just picked their video from a search for wifi fixing on Youtube)
The video shows the wifi chip replaced.
http://youtu.be/H33GpWr7pGg
Should Apple give free of charge wifi chip repairs to out of warranty 4S's?
===================================================================
General troubleshooting steps:
1.) Router set to 802.11n only, 20MHz only, WMM enabled, security disabled.
2.) Use PC's wifi to scan your environment. Do you see any wifi routers that have strong signals? Do you see any wifi routers that have similar names as yours?
3.) Does your router have a fancy SSID? Try a simpler name. Instead of "Tony's Router", change it to "TonyRouter". An inocent space can be a source for problem.
4.) Set your iphone's name to something simple and short. Instead of "Yvette's iPhone4S", set it to YvetteIphone4S". Removing the apostrophe actually fixd the wifi grayout problem for some people.
5.) Site closer to the wifi router. Wifi routers can die too. I've had trusty old routers that seem to work fine everyday then start to act up. Some days ok, some days can't keep a connection.
Best wishes.
