Swapped motors in an 05 MDX SAME 3.5L DONE NOW WONT CRANK...ECU?must i flash & domyself

What is your question?

ALL LIGHTS WORK JUST NO CRANK...DID FLASH GREEN KEY BUT FOUND MASTER KEY AND IT ONLY COMES ON IN NETURIAL.?checked every possiblity but with no luck anyone that's done this plz inform me.& where can i sell this used 3.5l was running but had bottom knock

What makes this problem better or worse?

Does nothing no sound no drain battery got charge but old battery

How long has your 2005 Acura MDX had this problem?

Since installed new used motor