2018 MacBook Pro randomly losing WiFi connection

So, after more analysis I found this issue only repeatable when I had ANYTHING plugged into USB-C

This hard to find article explains the problem. https://support.apple.com/en-au/HT201163

If your USB device has a cable long enough that you can move the device, place it away from your Mac—and make sure not to place it behind your Mac, or near the hinge of its display. The antennas for Wi-Fi and Bluetooth are located there, and USB 3 devices placed there might interfere with your wireless connections.

Some Genius decided to put the USB-C ports right next to the WiFi antenna. The noise for a in proximity USB-C device can cause the issues reports. Sounds like a significant design flaw IMHO. Fixed by using a non-apple USBC hub with a longer cable than the apple designed USBC dongle. Also have USBC extension cables on order.

Unable to see ARP broadcast UPDATE:

I tried to kill process called config which only sent new ARPs. However it couldn't see broadcast.

After reboot everything worked smoothly but after few hours same issue. Broadcast has stopped coming. I have started to suspect 802.11 authentication (just a guess). I changed encryption from AES to TKIP/AES on the router and suddenly all broadcast appeared. I doubt there is error in the router cause older macbook can send it's own ARP which other macbook can't see.

Solution:

Try to change encryption on the router to TKIP/AES.

Will report back if this doesn't work.

https://imgur.com/a/lwRXBRB

After discussing with Apple support, a solution for a similar problem seemed to have solved this for me.

My issue

Brand new MBP '13 (2018) Mojave 10.14.2, bought and opened 2 weeks ago. I began having WiFi problems, where every once in a while my connection would drop (in undefined intervals, sometimes every few minutes, sometimes once in an hour). My Mac still seem to show as if I am connected to my network, it's just that I didn't have any internet connection. I found out that by turning off my WiFi connection (clicking the WiFi icon in the top bar and then selecting "Turn WiFi off"), and then right away turning it back on would solve it, but this is not a long-term solution, I want to have a steady connection throughout the day.

What solved it for me

After confirming that the issue is there by monitoring it in Wireless Diagnostics (and losing it after 20 min):

- Disconnected from my WiFi (hold Opt then click on WiFi icon > "Disconnect from [WiFi-Name]"

- Went to System Preferences > Network > Advanced

- Selected both the 2.4Ghz and 5Ghz networks > Clicked on the minus below to delete them from the list

- Moved over to the TCP/IP tab > clicked "Renew DHCP Lease"

- Rebooted my Mac

Again, not certain if it'll do the trick or not, and don't want to talk too early, but I've been running the diagnostics monitoring for 24 hours now and did not lose connection still.

Hope this helps someone out there.

Cheers.

Start a ping from terminal to your default gateway. Keep the terminal open.

When you notice the loss of internet connectivity via regular activity, look at you ping window and see if the ping responses get lost.

Then option-click the Wi-Fi icon on the menu bar and look at the RSSI, Noise, and Tx Rate while the network connectivity is still down.

Please se post the results here.

I've been debugging a problem with my VPN client constantly reconnecting, along with poor WiFi performance. After much digging, I came across an excellent article - although written for Yosemite and iOS8, it still seems to be relevant to Mojave, especially with a newer WiFi chip in the 2018 MacBook Pro. https://medium.com/@mariociabarra/wifriedx-in-depth-look-at-yosemite-wifi-and-awdl-airdrop-41a93eb22e48

The author wrote a program that essentially just issues a command and keeps it enforced. You can try it manually in a terminal window: sudo ifconfig awdl0 down

To reverse the command, type: sudo ifconfig awdl0 up

He gives a great technical explanation, so I won't repeat it here. The command disables a virtual network interface that's used for ad-hoc WiFi by features like Airdrop; I personally won't miss them. So far, I've gone from losing my connection 20 times an hour to being stable for 3+ hours.

Another Update: Well, that was very obvious! Just a few minutes after I reactivated the auto unlock with the Apple Watch, I lost the Wi-Fi Connection again. At least an automatic reconnect happened. But while the macOS Wi-Fi Diagnose was collecting the data, the Wi-Fi crashed again and stayed offline. I collected some additional data with a provided tool from Apple Support and let the Wi-Fi disconnected.

Magically, right after disabling the auto unlock again, the Wi-Fi connection was automatically re-established. I guess there is no better proof that we found the cause. Thanks to sirozha for the hint!

I provided all the data to Apple and I'm very curious what they'll respond.

Well it's been two weeks now and no issues with connectivity since I turned off the "Allow your Apple Watch to unlock your Mac" feature. For me, it must have been that feature that was causing my problems.

Hopefully Apple with find out why the issue is occurring and get it resolved, for now I'll unlock with TouchID.

I was the one who suggested that the problem could be related to either the Apple Watch (with the "Allow your Apple Watch to unlock you Mac" feature enabled on a Mac or to the Apple TV's AWDL (Apple Wireless Direct Link) feature enabled that allows one to Airplay directly to the Apple TV without being on the same Wi-Fi as the Apple TV.

Initially, I had the issue with the Wi-Fi icon going gray and losing the Wi-Fi connection on the 2018 MacBook Air when I bought the MacBook Air in December of 2018. My Wi-Fi is used on Ubiquiti UniFi APs. A few UniFi firmware upgrades later (some time in January 2019), the issue changed from the Wi-Fi icon going gray (and requiring a manual intervention to connect to Wi-Fi) to Wi-Fi icon staying the same (showing connected) but having a sudden loss of IP connectivity. Yet a few moreUniFi firmware upgrades later, the "sudden loss of IP connectivity" issue was resolved, but what remained was a gradual degradation of Wi-Fi access rates with the Tx rate dropping to as low as 13 Mbps and staying that low. This affected the Wi-Fi throughput dramatically, which was proven by running iPerf tests.

After my hunch that the issue could be related to the "Allow your Apple Watch to unlock you Mac" feature enabled on a Mac, I continued to use this feature even though others reported that turning off this feature fixed their issues. I continued to experience the gradual degradation of Wi-Fi access rates for months, but finally, about a month ago, I decided to turn the "Allow your Apple Watch to unlock you Mac" feature off on the 2018 MacBook Air. Since I did so, I haven't noticed any issues at all with the Wi-Fi connectivity, and neither do my Wi-Fi access rates degrade anymore on the 2018 MacBook Air.

Because I consistently had all the Wi-Fi issues described above, and especially because the Wi-F access rates consistently degraded and caused issues for my work, I can attest that turning off the "Allow your Apple Watch to unlock you Mac" feature at least fixes the issue with the degraded Wi-Fi access rates. As for other problems, such as the Wi-Fi icon going gray, this is probably a different issue (which may or may not be related to the Wi-F access rates degrading), and I think that issue is caused by some sort of incompatibility in the behavior of the latest Macs and some Wi-Fi routers/access points or the firmware running on them. So, I would recommend first upgrading the firmware on the Wi-Fi router / access point, and if that doesn't help, trying a different Wi-Fi router or access point. I can attest that with the latest stable firmware releases from Ubiquiti, UniFi access points, such as UAP-AC-HD and UAP-IW-HD do not have the problem with the 2018 MacBook Air that would cause the Wi-Fi icon to go gray or for the Wi-Fi to appear as connected but suddenly losing IP connectivity.

Try this...

RichardFoo

User level:

Level 1

(4 points)

Feb 15, 2019 4:24 PM in response to TimsTech

I've been debugging a problem with my VPN client constantly reconnecting, along with poor WiFi performance. After much digging, I came across an excellent article - although written for Yosemite and iOS8, it still seems to be relevant to Mojave, especially with a newer WiFi chip in the 2018 MacBook Pro. https://medium.com/@mariociabarra/wifriedx-in-depth-look-at-yosemite-wifi-and-awdl-airdrop-41a93eb22e48

The author wrote a program that essentially just issues a command and keeps it enforced. You can try it manually in a terminal window: sudo ifconfig awdl0 down

To reverse the command, type: sudo ifconfig awdl0 up

He gives a great technical explanation, so I won't repeat it here. The command disables a virtual network interface that's used for ad-hoc WiFi by features like Airdrop; I personally won't miss them. So far, I've gone from losing my connection 20 times an hour to being stable for 3+ hours.

I Found another way that solve this problem once and for good...

You go and delete every wifi that you have saved in your system one by one, making sure you made a note of the passwords you need, then you add only the ones you need most from the beginning.

After that I have no dropout again.

It seems Mojave or WiFi is confused sometimes, and with slight signal variations is looking to the available stations near by, and loosing connection to your broadband channel, and clearing and resigning things works fine.

For giggles, I installed Malwarebytes and ran a scan... as expected, it found nothing.

So far my solution has been to delete all my saved wifi connections and then add back. Since doing this, everything has been working fine. I will again update this thread in a week to let everyone know how it is going.

I had this problem for ages and finally worked out what was wrong.. I have an external hard drive and every time I had it plugged in my internet would go slow and then finally cut out. This is after months of me being on the phone to Apple trying to get them to figure out the problem, it being in store for 10 days etc... no one could work out the issue. So unplug your USBs and see if it makes any difference (might just be me, but I had this issue on 2 MacBook Pros 2018)

Well, I don't want to be too optimistic too early, but after disabling awdl0 I had no WiFi-issues through the day. So thanks again for the hint RichardFoo!

At first I disabled awd0 with the terminal but installed WiFriedX this evening... mutch more comfortable and works fine with Mojave.

If you want to check the status of awd0 just type "ifconfig awd0" in terminal. After a few other lines it should say "Status inactive" and vice versa.

Let's see if WiFi works another day without awdl0.

When the IP connection disappears, nothing gets logged in WiFi.log. I had tested it.

We are dealing with several issues here, which may be related.

The loss of IP connectivity is not total in my case. If I have a continuous ping, i get occasional ping responses coming back, but the packet loss is massive (>95%).

I also have a gradual degradation of access rates when the 2018 MacBook Air is on battery power. This happens about 30-40 minutes after the MacBook Air associates with an SSID.

I’ve tried associating with two different APs by Ubiquiti. One is UAP-IW-HD (based on the Mediatek chipset), and the other one is the UAP-AC-HD (based on the Qualcomm chipset). The degradation of access rates occurs with both APs in a similar manner.

I haven’t yet experienced the IP connectivity loss when associating with the UAP-AC-HD, but I’ve only used it for a week now. The IP connectivity loss occurred several times per day when associating with the UAP-IW-HD.

A week ago (when I replaced the UAP-IW-HD with the UAP-AC-HD), I removed the 2.4 GHz band from the SSID on which my MacBook Air is associating, so this SSID is now 5 GHz only. This may be the reason I’m no longer experiencing the IP connectivity loss. I read of someone else using this technique to improve Wi-Fi connectivity issues a few years ago with earlier MacBook Pros, so I did the same a week ago.

I’d suggest you guys try to have two separate SSIDs: one for 5 GHz and the other one for 2.4 GHz to see if it takes care of the IP connectivity loss issue.

However, the gradual degradation of access rates issue is a serious one too because it results in throughput degradation as well. When my Tx rate shows 13 Mbps, and I run the WiFiPerf utility, my upstream transfer rate is between 2 Mbps and 10 Mbps, which is dismal. After I toggle Wi-Fi off and on, and my Tx rate goes back up to 866 Mbps, the transfer rate, as measured by WiFiPerf, is as high as 480 Mbps. The difference between 10 Mbps and 480 Mbps is 48 fold.

Apple should be seriously looking into this issue. I think it may be related to power saving algorithms while on battery power, as it doesn’t manifest itself in my environment when the 2018 MacBook Air is plugged in the wall power.

I'll say it again...

I've made no changes to anything except my MacBook Pro, which I disabled the unlock with Apple Watch feature. So far, this seems to have resolved MY issues. I'm not worried about the AppleTV using AWDL because it works fine. The MacBook Pro is the only device in my home with issues.

I will not move to make changes to other devices unless this step does not work. Time will tell.