All my lenses which used to work fine on the D70 now give the fEE error. All are locked at the minimum aperture. I have tried cleaning the camera and lens rings, a hard reset, and pushing the DOF button multiple times. All lenses connect OK on D5100, and newer lenses for the D5100 connect OK on the older D70. Any ideas?
By a process of elimination if the lenses still work on other bodies, they are OK.
Since no lenses now work on the D70 and they all did previously then that has probably failed.
Since you've cleaned the contacts the only thing is that the mechanical aperture control may be stuck and failing that it would need specialist attention and would probably be cheaper to replace than to repair.