Hello, I came across this forum after having the same issue with an F3 I just bought. I am new to Nikon 35mm and can't figure out what's wrong. Like you I took a few good shots then suddenly the display is all nonsenseŚwith the "-+" signs and giving either 1050, 1060 or 0 as the shutterspeed no mater if it's in auto or manual. Did you ever resolve the issue?