My NH TN85A tractor flashes three quick flashes, then a pause, then four flashes, a pause and one flash. The tractor appears to be in neutral, and will not move forward. It will move backward. Shutting off the tractor and waiting for a few minutes will allow the tractor to move forward for a short time, then the light starts flashing again and the tractor again seems to be in neutral. The clutch is very jumpy.