Neutral safety switch and alternator issues

[jreilly868]

Hello, i have recently put a new engine in my lexus ls430. the last engine had a catastrophic timing belt failure. it was unfortunate but i was able to get a used 3uz for $700. i’m currently having an issue after getting everything back together. my alternator is not putting out enough volts and i believe it is causing the neutral safety switch error code to pop up. i have no lights indicating what gear i’m in however the car will not let me start unless I’m in neutral or drive so i know the switch is ok mechanically . i have also checked the wiring and connector for it and it checks out. after doing an altlernaor test with an OBD11 scanner i found it is only producing 11.5 volts. i have a friend with an 03 430 so i swapped his alternator into my car. i did the test on his car with his alternator and it passed the test. however with his alternator in my car it still is not producing enough voltage. i also used his battery incase my battery was bad however the results remained the same. the code i am getting is p1780 for the NSS aswell as a cylinder 5 ingniter circuit. i’m not sure if those are related but i am almost positive the charging issue is what’s causing the NSS issue but i can’t figure out why the alternator isn’t putting out enough volts. i have no aftermarket stereo, amp or anything. it was my first car and id love to get it back on the road but i just don’t know where to start. i have check all grounds. could it be a relay or fuse? i appreciate any suggestions 

[McBrian]

Hipshot is wiring. Clean and check all connectors. Treat with DeOxit D100. Look for breaks or shorts. Also look for a missing connection working back from the NSS(?)