(FIXED) 2006 Hyundai Sonata intermittent crank/ no start.

Good Afternoon guys, 

I currently have a 2006 Hyundai Sonata 2.4L 4 CYL intermittent crank/ no start. 
When the car is started up first thing in the morning, it runs fine throughout the WHOLE time that the car is on AND NEVER STALLS. However, if you go shut off the car, and try to turn it back on, it's a hit or miss whether it'll start back up or not. KEEP IN MIND WHEN READING BELOW THAT THE CRANK, NO START HAPPENS INTERMITTENTLY.

WHAT I FOUND:
*** NO DTCS PRESENT ONLY THE EVAP LEAK DTCS WHICH IS IRRELEVENT***
1)Suspected failing crank sensor, inspected waveform through signal wire, when i duplicated the concern I noticed when it was cranking, there was no waveform.
2) Replaced crank sensor, turned on vehicle, shut off ignition, and after a couple of key cycles, crank, no start condition again.
3) The crank sensor has CKP+, CKP-, and signal. The crankshaft positive wire (pin 1) has 12V on IG-ON. and has 0v with IG-OFF.
4) I can duplicate the concern without having to turn the car on, I cycle the key, and when the crank, no start condition occurs, is when I see 0.5V at the (CKP+)
THIS WOULD EXPLAIN WHY THERE WAS INTERMITTENTLY NO CRANK SIGNAL WHEN CRANKING THE ENGINE, BECAUSE THE 12V FEED IS NOT BEING SUPPLIED BY THE ECM TO THE CRANKSHAFT POSITION SENSOR, BECAUSE THE MAIN RELAY IS NOT BEING GROUNDED TO TURN ON

MY SUSPICIONS/ INSPECTIONS
1) I noticed the engine main relay does not power on when the condition occurs (ecm is not grounding the circuit), and thus the engine ECM does not send the 12V feed to the crankshaft position sensor (which is powered by the SNSR1 fuse)
2)When the condition occurs the CKP+ Will remain on 0.5V no matter how long you leave it on IG-ON, but the moment you cycle it, it will read 12V again. 
3) When the condition is occuring, my Autel scanner no longer communicates with the engine ECM 
4) I'm suspecting either a ECM GROUND WIRE, ECM INTERNAL GROUND or a IMMOBILIZER RELATED ISSUE. (it uses a transponder key, the light flashes red on the dash and when I put the key in it no longer flashes.) 
5) I'm wondering if this will be a valid test. So the immobilizer sends a key code to the ECM if the key is matched or not, if it is not, the fuel supply will be cut off which i'm ASSUMING is through the ECM Fuel pump control wire (controls ground to the fuel pump relay) ..(when the crank, no start condition occurs, the fuel pump is no longer heard priming).

6) Once I duplicate the concern and evidently see 0.5V i'm thinking if I manually ground the Engine ECU wire that provides a ground for the MAIN RELAY, and in theory, if the key is indeed reading correctly, the fuel pump relay should be grounded by the ECM and the car should start. Would this be my final test to determine if I need a ECM or if i'm dealing with a immobilizer issue? I'm trying to pin point the ECM as far as I can.

PLEASE REVIEW ATTACHED DIAGRAMS TO AID IN UNDERSTANDING.

When you no longer have communication with the ecm do you have a 5’volt reference? If you have a scope or test light your going to need to make sure your not losing a power or ground feed to the computer.

I'm going to check when I get the car again, I have not checked ECM power and grounds WHILE the condition is occuring. According to AllData, the 5V reference is only supplied to the Acceleration Position Sensor, A/C pressure sensor, and power steering sensor. Doesn't seem like any of those would cause a no-start.

I didn't have any good input here but I wanted to share my findings. This vehicle doesn't have the SMARTRA immobilizer, that is only for canadian vehicles which made my diagnosis a lot easier. I indeed did have ignition sw signal to the ECM (12V IG-ON) I had all ECM B+ powers and IG-ON ECM powers (except for one that is a ECM fuse powered by the main relay). I verified my 3 ECM grounds were ok, I inspected the pins on the ecm, I verified there was no corrosion nor bent pins. I tried to jump the Control circuit to ground (to turn on the relay) and the vehicle did not turn on, this test was indeed not valid. The ECM MUST provide the control ground in order to turn on the main relay AND the fuel pump relay, if it is jumped to ground, it will only turn on the main relay but NOT the fuel pump relay (also controlled by ECM ground). At this point I verified I had my inputs, but my main relay control circuit (output) ground was not given.

FIX:
Replaced ECM, condition no longer occurs.