To the best of my knowledge the inhibit clutch interlock relay will not allow the car to be started while the automatic transmission is in gear. (ie-must be in neutral or park)
On manual cars there is a lockout relay which either operated the inhibitor relay or functions by itself.
This is a general answer, perhaps someone has a more Nissan specific.
For my 1994 Nissan pathfinder, which as im told is identical under the hood, the clutch interlock relay is on the sidewall by the battery. Grab a Chilton manual that covers that year, they have a good picture of it but mine is blue and the second closest relay to the battery itself.
The Inhibit relay ( same as neutral safety interlock relay) for 1996 Nissan Sentra is located: Under the hood, inside the big relay box, 3rd relay from the front (also labelled "Inhibit ) on top of the relay Box which is the bigest electrical (Black plastic compartment you'll find under the hood. If you put you fingers to feel the top of the relay, you'll feel the "click " the relay produces - the relay controls one NO & one NC switch. Yes, the inhibit relay has a lot to do with the starting circuit, it prevent the vehicle to start when car is in gears other than "Part" and "NEutral".
How to replace a clutch interlock switch on a 1997 Ford Ranger XLT
The clutch interlock switch is located under the dashboard and is similar if not identical to the brake light switch. you will find it where the clutch pedal extends to the furthest down position under the dash. It prevents you from starting the vehicle without depressing the clutch thus preventing starting up in gear, its a safety issue if someone is standing in front of you when you do it you will run them over, but if you need to just cross the wires.
Clutch interlock should only prevent you from cranking the starter without the clutch depressed. You should be able to push start with this malfunctioning since the rotating motor is doing just what it would be if the starter worked.
Clutch interlock switch may be misaligned or faulty.
thats the relay to engage the a/c compressor clutch
AC Compressor clutch relay may be stuck. Remove the relay and see if the clutch releases.
If you turn the ignition to the on position, and then press the interlock button, you don't have to press the clutch pedal down to start the truck.
BAD RELAY answer bad switch bad relay and most likely, bad clutch
The fan clutch is a mechanical viscous drive and does not have a relay.
It doesn't have one, it has a switch on the clutch pedal. It also has an interlock switch on the dash, turn the ignition switch on and press the interlock switch and it will bypass the clutch switch.