Having trouble with van not starting. It's not the starter, the battery...all of this has been thoroughly checked. Seems to be related to the automatic entry system. Can I just "unplug" this system?

Sounds like a bad battery.

check your battery make sure terminals are clean and corrosion free . put a charger on your battery to make sure it is charged fully then see if it starts easier if it does great and if it happens again get your battery tested its either your battery altenator or starter relay

have battery retested-or ac electrical for parasite drain

Check relays,check all eletrical connections
check and see if you have current to starter soleinoid

Know this problem was posted several years ago, but having same issue with my 2008 Nissan Rogue. We've tried everything short of having the battery replaced, (including charging it), and nada. So, tomorrow morning, that'll be our next move. Sucks, but best thing to die. Much rather than than an alternator, starter or solenoid.

When the van refuses to start, have you tried to jump start it? If not, I would suggest you do, because it would allow you to rule out the battery and alternator (or at least be relatively confident that they are good) if the van DOES NOT start when you try to jump start it, then it would be either the starter/solenoid or in the engine.

Thanks for choosing FixYa and welcome. Since you have power inside the car, the battery and power connection should be good. You still want to make sure you have the best possible connection because if the starter isn't getting the correct amount of volts, it won't turn. So clean your battery terminals and post to make sure. Check your ignition fuse too. It should be labeled and shouls be located in the engine compartment fuse box. You may have a bad starter if the two steps before check out. You can take a hammer or pole, just something to make contact with your starter. You want to tap it five to seven times. Then try to start the van. If it starts, you have a bad starter and need to get it changed. I am thinking it is the starter because you have been having starting problems. Hit it and see if your van will crank up. Let me know what happens.

Going to need more info. Does the car turn over and try to start, or is it simply dead when you turn the key?
For the former, it could be spark plug/fuel pump related. For the latter, it is most likely a power (battery) issue.

Check your battery voltage and charging and the cable connections then unplug the ignition starter wire from the starter and try to jump the starter at the starter if it works then you have a voltage supply problem could be the ignition switch if it doesnt work that way the starter solenoid contacts are burnt you will need a starter

have the van checked for proper fuel pressure, also have the electronic engine control odule checked for trouble codes.