I'm posting this here as an FYI since I could not find any useful information on this.
This past Saturday I took my 2005 Outback to get its original battery replaced. I chose Advanced Auto and went there to pickup my new battery and have them swap it.
The salesman that assisted me hooked up a battery booster device to the OBD port under the dash then proceeded to replace my battery.
Firing up the car yielded a solid 'CHECK ENGINE' light with a flashing 'CRUISE' light.
I thought maybe the car's computer threw a code when it sputtered earlier that morning as I tried to start it with a weak battery.
I hooked up my scan tool to the OBD port hoping to see what the problem was and to clear any codes, since the car had been running flawlessly before the battery swap.
My scan tool would not power up. I know the car is supposed to provide power to the scan tool, so I decided to find out if there was a fuse protecting the OBD port. Going through my owner's manual and looking through the fuse box schematics yielded no information on a fuse for either the cruise control (which really wasn't the problem) or for the OBD port.
Well, folks in my 2005 Outback I found a 7.5 Amp fuse in the engine compartment fuse holder. It was blown. This fuse protects the OBD port and once replaced, my OBD port was functional again and the 'CHECK ENGINE' light with the flashing 'CRUISE' light was cleared.
Hope this info may be helpful.