I have 2015 2.4 equinox, just rebuild the engine put back into car, now no start no crank no communication with ecm with scanner,

No communication with ECM sounds like a data link issue, such as wire or blown fuse - or no electrical power. That's where I'd start. Since you've done some major repairs, it's absolutely impossible to guess what wiring or harnesses may have been left off or loose or have been improperly routed, hooked up or damaged. I'm sorry to say that it'll take some deconstruction of the work done to figure out what's going on. But again - if you're saying there is no communication with the ECM, start with electrical power and fuses first. https://repairpal.com/auto-repair-near-me Click the link or call us at 877-913-1554. We'll gladly find you a certified RepairPal shop in your area.