ls1b car won't start without flashscan V2 plugged in

My 2001 camaro with ls1B ecu won't start unless the flashscan v2 us plugged in. I have tried to do a full flash and it says it's successful. I put the same tune on a second ls1b ecu in the same car and nothing changed. Thanks in advance for any help I get with this issue.

Check your ground wires on the back of the driver head. Every Time I have seen that exact same thing one of those grounds was broke.

+1

( the V2 is completing a missing/broken ground connection )

I'll have to check that. Thanks very much!