My Nikon N55 was having intermittent DX sensing issues. This was hard to track down, because there is no indication of the ISO that is being sensed. The way I could tell is if I put an empty DX cassette in the camera, just before it flashes ERR, it will show the exposure for a fraction of a...
FWIW, I have three N75's also, plus some N70's. These cameras are now disposable - not worth repairing.
I like the 28-70 G lens for snap shots. Pretty sharp, light and compact.
The motor winder is nice too - uses AA's.
This reminds me of the time my buddy asked me to bring my Ford Diagnostic Scanner up to his place so he could test his truck with it. He had a 1978 Ford pickup. He thought I would get the joke, but I didn't. Ha. He was a patient man.