6 Replies Latest reply: Feb 29, 2012 6:20 AM by FrederikY
FrederikY Level 1 (0 points)

I have an iMac 2011 3.1 GHz.

The Ethernet Port works (sometimes).

But sometimes (every 1-2 Days), the Ethernet Port suddenly "turns off" (after a restart).

During this phase the iMac says "no Ethernet Cable Connected" and I am unable to open a new Ethernet access in preferences/Network.

On top of that it says in "Hardware" "NO ETHERNET PCI CARD INSTALLED".

Then I have to do a "PR-Reset" or a start holding down "SHIFT-Key" to bring it back to work.


I am totally confused.

The Ethernet port semms to be OK, I think this could be a software-Bug?!?

iMac (27-inch Mid 2011), Mac OS X (10.7.2)
  • Paul_31 Level 6 (13,655 points)

    Someone on here recently had problems with an ethernet port that stopped working. I believe an SMC reset seemed to fix it.


    SMC Reset

    1. Shut down the computer.
    2. Unplug the computer’s power cord and disconnect peripherals.
    3. Press and hold the power button for 5 seconds.
    4. Release the power button.
    5. Attach the computers power cable.
    6. Press the power button to turn on the computer.
  • FrederikY Level 1 (0 points)

    Thanks for your answer.

    I'll try that tomorrow.

    I hope that it will clear my problems!

    I'm going to answer if this was helpful.

  • Paul_31 Level 6 (13,655 points)

    Thanks - let us know how you get on.

  • FrederikY Level 1 (0 points)

    Sadly it helped not.

    Same Situation: "No Ethernet PCI Cards are installed".


    But in terminal:

    netstat -I en0

    • Name  Mtu   Network       Address            Ipkts Ierrs    Opkts Oerrs  Coll
    • en0   1500  <Link#5>    12:8a:sx:a0:b7:a3    30869     0    23025     0     0
    • en0   1500  imac-119add fe80:5::134a:ddff    30869     -    23025     -     -
    • en0   1500  192.168.2      30869     -    23025     -     -

    -> so the Ethernet Port seems to be OK.


    BUT "ping" is not possible.

  • FrederikY Level 1 (0 points)

    Well I just brought my iMac to an Apple Reseller on Tuesday, and got it back today (Friday).




    They replaced the LogicBoard.

  • FrederikY Level 1 (0 points)

    I have an new problem, let's go again to the Apple Reseller

    This time the display is darker on the left side