Tue 04-Jan-11 04:20 AM | edited Tue 04-Jan-11 04:22 AM by TomCurious
Sorry you're having trouble! The D40 is such a nice camera. Can you tell us what exactly goes black? The viewfinder - you cannot see the scene thru the viewfinder/lens anymore? Or the LCD on the back does not show the image review anymore? Is the picture still recorded onto the SD card and you can take more pictures? Some more info will help us give advice.
By the way, this should be posted in the D60/D50/D40 forum where fellow D40 owners can see it so you might get more help there.