iMac Firmware Update Failed, Constant Restarting

[rmbrown09]

27" 2010 iMac, on 10.6.8

Tries to apply the firmware update but apparently something has happened because it goes a small ways and just turns the computer off. It cannot break from this loop.

I cannot get it to boot from a DVD or show me the drives by holding option. I can however get into command line using cmd+s

Any tips??

 

[derbothaus]

If someone with an iMac can verify the location of the firmware file (/Utilities/?) you could boot into single user mode, mount the file system and rm the file. No payload to pull from but that may still keep the cycle going. Maybe remove the file then PRAM zap and cross fingers.