Hello,
Just bought a qx56 as is. First issue I have to address is the key not turning along with the steering wheel. Car recognizes smart key. Occasionally there will be an error message on the dash with a key lock picture, a left pointing arrow above it, and the work lock above that. No combination of turning the wheel with the physical key in or out of the cylinder will let either budge. Doing research shows that maybe the part number D8701-7S000 is at fault if im right. I also have the 4,000+ page factory manual and was wondering where the plug for the "Steering lock unit" is. Book shows it as a for pin connector but where and which one is it?
Thanks for all the help!

Welcome aboard!

Wonder if it was stolen and the actual key is wrong or the immobilizer was defeated?

Make sure battery voltage is perfect and grounds are all clean and functional. Lots of ignition lock issues can be traced back to insufficient voltage or a crappy ground.

Steering lock unit should be on the column inside all the plastic shrouding.