What is happening to my Nikon FE2?

I just got a Nikon FE2 camera, but I'm having some trouble using it since I'm new with a film camera.
When ever I shoot with a "M250" (what is that?) shutter speed, it works normally; the shutter goes up and down. But whenever I shoot in Automatic, or any other speed the shutter seems to be sort of stuck or something and I see black on the viewfinder. The only way to turn it back to the way it was is by setting the shutter speed to "M250"

What is happening and how can I fix this?

M250 does two things (as well as being a shutter speed setting);
a) flash synch speed.
b) Mechanical (M) backup - the only mechanical speed this camera has.

Try to shoot without batteries at any other speed and the mirror locks up.

I'd suggest fresh batteries (2xLR44 or 1XDL 1/3), which will probably cure the problem. Manual here:

http://www.butkus.org/chinon/nikon/nikon_fe2/nikon_fe2.htm

The "M250" setting is a "mechanically" controlled 1/250 of a second setting that can be used in an emergency when your battery is dead and the light meter won't work. The meter will not function at the M250 setting.
When you have the FE2 set for "A" auto operation, you set the f/stop and the electronically controlled circuit will automatically set the proper shutter speed. To use the manual mode, just turn the dial to any of the other 16 shutter speed choices. Using different lens openings in conjunction with a manual shutter speed will allow for different depths of field and over/under exposures.
Make sure the battery is okay and that the lens you're using is a Nikkor lens.
If you didn't get a operators manual for this camera, here are some links where you can read or download the FE2 instruction manual.

http://search.aol.com/aol/search?query=Instruction+manual+for+a+Nikon+FE2%3F&s_it=keyword_rollover

The FE2 is electronic with one manual setting, 1/250s shutter speed. Make sure you have a fresh set of batteries installed for the rest of the settings to become available.