What do I do if my 2005 Nissan Maxima engine is locked up and will not crank

Check the timing belt and coil pack.

to machine the crank and get another rod --set of big end and mains-- probably a rebore-- pistons --rings --labour Time off road- It will be cheaper to fit a reconditioned short motor so check around for one from an accredited engine remanufacturer.

crank sensor is at the bottom of the crank pulley. right under neith the pulley is a 2 wire sensor bolted to the engine with 2 bolts.

you shouldn't but you will have to get your doors and trunk locks re-keyed you could keep your old keys for those locks should call dealer they would probably be happy to advise best way to do this not sure this is absolute on your car but have done this on a few others

If the engine block is of the same family, then it is doable, but even then there will be snags...ALWAYS.

hold lock and unlock buttons on your key fob simultaneously until lights flash and horn beeps.this should do it.

this should be known issue at your nissan dealership, was a recall in most countries to replace all 4 door lock actuators. if the vehicle is out of warranty this may not apply.
The acuators are a sealed design and cannot be repaired, can only be replaced with new ones,

If your key is not programmed for the car, then it will have this issue. I bought a 99 Maxima 3 weeks ago. One of the keys was programmed and worked perfectly. The other would turn the car over and stop it immediately. If you do this too many times without the key being programmed from the dealer or another source, it will erase all keys that are programmed and lock down the ignition.

i have a 1998 nissan maxima when the engine is cold the engine will cut off when you first crank it. It will cut off but i can usually get it going the second time. After engine warms up car runs great. Why does this occur

All four door lock actuators were bad, fussed enough with dealer , they are fixing for free, save me $1600!