Canon EOS 30D exposure metering not working

My wife dropped the EOS30D together with a Speedlite flash gun - and initially the only damage appeared to be the broken hot shoe foot on the Speedlite. To my alarm I have discovered that the exposure metering on the camera is not working as expected. In all full or semi-automatic modes the camera wants to use an exposure in excess of several seconds. The exposure varies dependent on whether the camera is pointed at dark or light subjects, so there still seems to be response from the sensors, however it appears either the metering sensor or the electronics are providing confusing data... I came to this conclusion after trying out various other lenses I own and with any of these the camera stillexhibited the same problem, i.e. I have eliminated the possibility of the fault being caused by a damaged lens.

I can use the camera in manual mode, which is quite annoying so I might have to send the camera in for repair. On the other hand, given that the expected cost of repair might far exceed the camera's re-sale value, and being a bit of a technology geek myself, I was thinking about attempting to fix this problem on my own. I expect the only thing that could have happened when the camera fell is that either some circuit connection or the sensor itself got dislocated. I doubt the camera being dropped would have actually physically damaged any component inside, as these are usually firmly fastened with screws and especially as there are no marks on the surface of the camera indicating any problems whatsoever.

If there is anyone out there who could point me in the right direction, i.e. where is the exposure sensor and ambient light sensor located and where are the circuits processing the signals these sensors produce. I did find a good disassembly guide here: http://mbignell.com/2008/08/02/disassembling-the-canon-eos-30d/ so that could be the start of it..  Any help or information is much appreciated!

Cheers,
-Stefan