17478 Views 5 Replies Latest reply: Jan 26, 2009 7:11 PM by golferguy357
A USB message like this will typically indicate either a bad USB cable, a bad device that's plugged into the USB port or the port itself is bad.
On the left side of the MacBook (I refer to it as the I/O board) you also have a FireWire 400 port and Ethernet port. Are those working correctly? Secondly, if you plug in a USB-based device (such as an iPod or other product) and launch System Profiler (go to USB) does it show up as a connected device?
It would seem to me that the potential point of failure (if you're getting the message with nothing plugged in and after resetting the SMC & PRAM) is the logic board. But again, I'm merely speculating via process of elimination.
Are you near an Apple Retail Store or Authorized Service Provider? They have more extensive diagnostic tools and can also serve as a point of repair should the machine require it.
No, the message comes up each time when the computer is booted, without anything plugged into any port. The firewire port is working. I have also suspected the failure of the USB ports or even the UBS unit on the logic board. Certainly, I also suspect the power management failure too.
As you suggested, I plan to visit the Apple store for advice. Unfortunately, my daughter has this one for two years and does not have an extended warranty on it. If something wrong with the USB unit and if the USB unit cannot be replaced separately, the cost to replace the logic board is not cheap at all.
This is the first time that I know that an Apple computer fails so soon. I have used Apple computers since its first or second line of production. The earlier models were still operational when I mothballed them. I wonder the quality of the Apple products is at issue that might be because Apple uses more foreign parts.
Your daughters computer has fried USB ports. These are not expencive to replace and should fix the problem. If the rest of the computer is functioning normally, it should be a simple fix. Did you try a PRAM reset?
Instructions for PRAM can be found here:
Also, make sure you did the SMC correctly. Even though the SMC has almost nothing to do with the USB ports it still may help.
Instructions for SMC are here:
Hope this helps!
I have been struggling with this USB over current notice for a long time now. Every time I would log on the box would come up even when i didn't have anything plugged in to the USB ports. The notice would also keep popping up after i clicked out of it. It came up almost once every minute which was very annoying while working. I found this article and reset the PRAM and the computer has been perfect ever since. I also used to have this problem where when i clicked on the bluetooth icon in the system preferences my computer would freeze up and i could never connect any bluetooth products. But, since this PRAM reset, the bluetooth has been working perfectly. This PRAM reset was a great help! Thanks