Why does the wifi only work intermittently?
I have a Late 2011 15" Macbook Pro with a 2.2 Ghz i7 with Mountain Lion. About a week ago, I started having wifi issues where the computer would suddenly disconnect from the wifi network and turn off the Airport Card. The indicator on the menu bar would still show that it was connected to the network, but the status in the Network preferences pane would show the card was actually off. The card could not be turned on unless the computer was restarted and plugged into the power adapter.
So far, this is what I have found out:
1. The computer will only exhibit this behavior if used as a portable. If it sits on the laptop stand on my desk and is not moved, then the wifi works perfectly. Once it is moved, everything fails.
2. If the computer is started up with battery power only AND not moved, the computer will not recognize the wifi card at all ("no hardware installed").
3. I have wiped the hard drive and installed different versions of OSX on the computer, but the issue still persists.
4. I have opened up the computer, made sure all the connections between the logic board and the Airport card and the antennas are secure.
5. Even when wifi fails, the bluetooth still works. If I am correct, wifi and bluetooth are on the same card.
6. And of course, I have tried multiple PRAM resets, SMC resets, anything I could think of.
Any help is appreciated!
I have now replaced the Airport card itself, and the problem went away for one day and has come back. The computer will not recognize the Airport card at all. I have made sure all the connections between the antennas are secure and the flex cable from the wireless card to the motherboard are secure. I am stumped now.