Ethernet port doesn't work on 2017 iMac

[gogreen1]

A few days ago, I noticed that my 2017 iMac's ethernet port stopped working. I know it's not the ethernet cable because when I attach it to my USB hub with an ethernet converter and plug it into one of my iMac's USB ports, I connect to my LAN and the internet just fine. I also tried rebooting the computer several times and restarting my router, all to no avail.

I read an article on 9to5mac about fixing a broken Ethernet port, but that article was from 2016, so I'm guessing it's irrelevant.

My iMac's wifi works just fine, but I like to use a wired connection on this computer.

Does anyone know how to fix this, or at least, how to determine if it's the port itself or a software problem?

Thanks.

 

[MacInWin]

Try an SMC reset. You can also go to System Preferences/Network and see what the status of the Ethernet port is. If good, it should have a green dot showing it's working and connected.

 

[gogreen1]

Thanks, Jake. I tried an SMC reset. Didn't work. Ethernet port status still red (not connected).

 

[MacInWin]

Ok, that was a good try. To eliminate mechanical issues, can you get a can of compressed air and blow a shot into the ethernet port to see if a dust bunny is in there blocking the pins and look in the socket on the Mac to see if any of the pins are bent or broken? Red indicates zero network sensing, which is normally a physical issue, typically cable, but you seem to have eliminated the cable with your other testing. It wouldn't hurt to try a different cable anyway, if you have one, just to be 100% certain it's not something intermittent in the cable.

Assuming the worst, is there any reason you wouldn't continue to use the hub for the connection, since it seemed to work?

 

[chscag]

You might also try a direct connection from the iMac to your router and at the same time, try different ports on the router.

If you have already done that, ignore this message.

 

[gogreen1]

Thanks, chscag. Different ports on the router didn't work.

MacInWin: I checked the port, and it look fine--no broken or bent pins, and no dust. I gave it a few shots of compressed air. Changing the cable didn't work.

I use a wired connection because my iMac is 2 feet from the router. This problem isn't a crisis because wifi is working fine. I don't absolutely have to have a wired connection--I just prefer it on my iMac.

I'm wondering if I should run some hardware and software diagnostics. Would that be beneficial? Could the recent Big Sur update have caused the problem?

Thanks.

 

[gogreen1]

I just ran First Aid and rebooted in safe mode--everything checks out.

 

[ferrarr]

I just ran First Aid and rebooted in safe mode--everything checks out.

Did the ethernet port work in safe mode?

 

[gogreen1]

ferrarr: The ethernet port did not work in safe mode.

 

[chscag]

Very likely a hardware defect with the ethernet port. What you can do if you really want to use the ethernet port is buy a USB to ethernet adapter and use that instead. You have three USB 3 ports on your iMac and as long as you have one free it can be used.

I believe Monoprice also sells a Thunderbolt to ethernet adapter. That might be a better choice since you have two TB 3 ports on your iMac. That adapter will be more expensive, however.

 

[MacInWin]

The first post says he has a hub already that has Ethernet. That should be sufficient, no need to buy anything new, unless I'm missing something.

 

[chscag]

The first post says he has a hub already that has Ethernet. That should be sufficient, no need to buy anything new, unless I'm missing something.

Yep, I missed that.

@gogreen1: Disregard my suggestions. Looks like you already have a converter that works.

 

[gogreen1]

Yeah, I do have a converter that works. I briefly looked into replacing the port, but it appears to be beyond my capability--I'm not eager to open up the iMac, desolder the port, and replace it. So I guess I'll continue to use wifi and live with the broken ethernet port. Things could be worse...

 

[chscag]

Unfortunately, later model iMacs like the one we both own are not easy to open and perform work on. Even though I'm an old retired electronics and computer repair tech, I'm not sure I would want to tackle the job.

 

[gogreen1]

YIKES!

I think I just fixed it! I went into System Preferences > Network and deleted the connection ("-" sign). I then clicked on the "+" symbol and added an ethernet connection and renewed the DHCP. VOILA! Back on and connected!

However, I stupidly deleted the 10/100/1000 connection, and it no longer appears as an option. How do I get that back?

 

[skays]

I just went through all of this on my 2017 iMac 27". No direct ethernet, but WiFi worked. Bottom line, determined the ethernet port on the back of my iMac inop. A friend let me use his ethernet to USB adapter. Used the adapter with my existing ethernet cable and plugged it into an available USB slot on my iMac. Worked fine. So I know the ports on my Netgear Gigabyte Access Point device and ethernet cable are fine.

Went on the Apple Store and ordered a gigabyte ethernet to thunderbolt adapter as I have an empty thunderbolt port on the my iMac. Received it in the mail, but it had the "older" shaped Thunderbolt connecter. Nothing on Apple's website provided this information at all, just that it was an ethernet to thunderbolt adapter. Called Apple who apologized and said Apple had changed their thunderbolt connections to a USB C type connection sometime prior to 2017 and offered to send me the correct adapter for free. Just received the adapter in the mail, but it is a Belkin Gigabyte to USB C adapter. Regardless...works fine, very fast and free.

 

[skays]

I just went through all of this on my 2017 iMac 27". No direct ethernet, but WiFi worked. Bottom line, determined the ethernet port on the back of my iMac inop. A friend let me use his ethernet to USB adapter. Used the adapter with my existing ethernet cable and plugged it into an available USB slot on my iMac. Worked fine. So I know the ports on my Netgear Gigabyte Access Point device and ethernet cable are fine.

Went on the Apple Store and ordered a gigabyte ethernet to thunderbolt adapter as I have an empty thunderbolt port on the my iMac. Received it in the mail, but it had the "older" shaped Thunderbolt connecter. Nothing on Apple's website provided this information at all, just that it was an ethernet to thunderbolt adapter. Called Apple who apologized and said Apple had changed their thunderbolt connections to a USB C type connection sometime prior to 2017 and offered to send me the correct adapter for free. Just received the adapter in the mail, but it is a Belkin Gigabyte to USB C adapter. Regardless...works fine, very fast and free.

and FYI...My iMac was purchased in early 2015 so it is over 4 years old. Advised to fix the port a logic board would have to be replaced to the tune of around $450...not including labor. So I opted for the ethernet adapter as I would probably be replacing the iMac in the next couple of years anyway. As an added bonus, the older Gigabyte to Thunderbolt Adapter works just fine on my 2013 MacAir Notebook. ?