iPhone Won't Connect to WiFi

Auteur : Alisha C (et 2 autres contributeurs)

What good is a smartphone without internet connectivity? No social media, no streaming videos and no hunting feverishly for that earworm of a song that you can't remember the name of at 3:00 am. So when the WiFi on your phone goes out, it spells trouble. This is often an easy fix, but even if it's not, here are some steps to get you back on the world wide web.

Before undertaking any of the more time-consuming solutions below, these are a few fundamentals to give a go.

Restart your phone. This could clear any minor software hiccups.
Toggle WiFi off and back on.
Forget the network in your settings by selecting it in the WiFi menu and clicking the Forget This Network button at the top. If you are not presently connected to the network, select the Edit button in the upper right corner and delete it from the list.
Perform a Network Settings Reset. Note: This will remove all presently known WiFi or Bluetooth connections. They will need to be connected again following this procedure.
Although it is rare, if you have a bulky case, remove it just to confirm it is not impeding the iPhone's ability to receive WiFi signals.

Before we start troubleshooting issues with your phone, it’s important to make sure the phone is to blame. Do a few quick checks to sort this out rather than delving into your phone’s innards.

Verify that other devices can connect to the network. Is your iPhone the only device affected? That builds a much stronger case for your iPhone being at fault.
Can your iPhone connect to other networks? See if you can use a public network at a local coffee shop, library or anywhere that offers WiFi for the general public.
Is your WiFi signal weak? A poor signal can cause an inability to connect or even detect that the network is present. If your signal is low, move closer to your router.
Verify you are using an up-to-date password. If you are getting an error message when you attempt to connect, it does not always specify that an incorrect password is being used. "Unable to Connect" could still mean your password is wrong.
If other devices are also experiencing issues, it’s more likely your network. Unplug your wireless router. Leave it unplugged for about a minute. Plug it back in and wait for it to reinitialize before trying to connect.
If power cycling the router doesn’t help, do the same for your modem. Note: Depending on your setup, the modem and router may be combined into one device—no need to try again if this is the case.
If your issue persists after this and multiple devices are affected, time to call your Internet Service Provider for assistance. It could even be as simple as an outage, but if not, their equipment may require servicing.

A Virtual Private Network, or VPN, is a great way to maintain better privacy while browsing the web. However, it can also impede your ability to get the web at all.

If you use a VPN, or app which claims to anonymize your web browsing, turn it off to verify it isn’t causing your connectivity issues.
Alternatively, you may need to turn it on, especially if you’re trying to connect to a public network. Some VPN apps have settings that will disable traffic to the web unless they are enabled. This can generally be disabled in the app's settings.
Check the app for updates.
Uninstall the app and retest if the issue is still unresolved. You may also need to check under Settings > General > Profiles and Device Management to make sure any configuration profiles associated with the app were removed.

Any software which contains errors can cause connectivity issues.

See if you can use the network elsewhere. Use a different internet browser, or check another app to see if WiFi is working there.
If WiFi works in other functions, open the App Switcher and close the problematic app.
Reopen the affected app and try to recreate the issue. If it reoccurs, check the App Store for updates and install them. Uninstall and reinstall the app if no updates are present.
If it is also unresponsive in other functions, this could be an Operating System issue. Use a PC with iTunes or a Mac to check for and install any updates.
To rule out software entirely, be sure you have a current backup, and restore your phone via a computer to ensure a fresh copy of the Operating System is used. This will delete all data on the phone. Try without restoring your backup at first to keep testing limited to a bare OS.
- If your WiFi works with the bare OS but ceases working when you restore your backup, try deleting any apps that were installed immediately prior to the issue arising.

Just like the FM radio in your car, WiFi uses electromagnetic waves to transmit signals. Also like FM radio, it requires an antenna to collect the signal and convert it into data your iPhone can interpret. Malfunctioning antennas could prevent your phone from even knowing there is a signal present.

Antenna issues are more likely to manifest as a weak or non-existent signal. This can result in an inability to connect to the network or frequently dropped connections.
Since there are several antennas in any iPhone, a visual inspection should be your first step. Use the Guide for your model and open the phone. Check for signs of liquid, heat, or tearing.
- Be mindful that an iPhone makes use of several other wireless communications types, so not all antennas are specifically for WiFi.
- Antennas tend to be located along the edges of the phone or may be part of other cable assemblies. Their locations vary by model. Consider any visible irregularities suspect and worth investigating.

If you have performed a repair recently, check that all the cables are seated properly and look closely at any places you touched during the repair.
The iPhone 8 and 8 Plus are especially prone to WiFi antenna damage due to their disconnection during a battery replacement.

The logic board is the hub for the vast majority of an iPhone's functionality. Any number of the small components on the board may have failed or become damaged, and it's safe to assume it's the cause if nothing else on this page has worked.

Grayed-out WiFi, or inability to enable WiFi, is a telltale sign that your issue is with the board. It may also be accompanied by Bluetooth dysfunction since the WiFi chip is also responsible for Bluetooth.
Check for obvious signs of a board issue - burned or cracked components, liquid residue, corrosion, or bend. If there are signs of liquid the iPhone Liquid Damage Guide might help.

iPhone 7 Plus WiFi chip

The WiFI chip is usually easy to identify on iPhone 8 and older models—use the teardown or motherboard guide for your model of iPhone to assist in locating it.
- Most iPhones newer than the iPhone X use a logic board which is actually two boards sandwiched together. The WiFi module is always on the bottom board and will not be visible. Issues on these frequently stem from a heavy drop or bend, causing the communication lines between the boards to sever in some places.
Replacing the logic board is often the most practical solution for a DIYer in this position.
However, contrary to popular belief, the board itself can be repaired. It requires specialized tools and microsoldering know-how. This is not something most people can do themselves, but many independent repair shops can do it for you! Ask around to find a board-level repair specialist near you.