Firewire glitch

Question

Hi;
After a power surge, I've lost firewire capabilities. The power is present; I can charge a device, but I cannot communicate or connect with any peripherals.

Answer 1

Billy Stidham,
Welcome to the Apple Discussions!
1. shut down
2. remove all Firewire peripherals from the eMac
3. remove the power cord from the side of the eMac (this removes the trickle current that modern electroincs draw even when nominally off)
4. wait at least 30 minutes
5. reattach the power cord
6. restart
7. open Applications> Utilities> System Profiler and check that the Firewire tab shows the bus as recognized
8. reattach your Firewire periherals one at a time, refreshing System profiler after each device. (If one particular device doesn't appear while the bus does, that device and/or its Firewire cable may be damaged.)
What kind of power line protection do you have? Cheap MOSFET-based surge protectors are essentially one-shot devices, with a nasty design that allows the 'protected' ststus LED to remain lit long after effective protection has been lost. While a good-quality multi-stage surge protector provides a safeguard against a power surge (the lab where I work is quite fond of Tripp Lite Isobar suge protectors), those provide no protection against power brownouts and outages. An Uninterruptable Surge Protector (UPS) from a reputable vendor such as APC is highly recommended. In the area I live, local computer and office supply stores often use the low-end 350mA APC model as a loss-leader to pull people into the store, with a net price of US$30 or less. While higher battery capacity is always desireable, and higher-end models include integrated cable and/or Ethernet protection as well as phone line, even a low-end UPS allows the computer to ride out momentary power outages. Connect the UPS to the Mac with a USB cable, and you can use Energy Saver to program it to shut down gracefully in case of longer outages.