2011 cxl 3.6l changed ecu now it wont start

[onuah]

I had just changed out my ecu because I was throwing false codes and the car wasn't letting me try to even start it well I had followed all instructions for the key reset after changing out my ecu and it just will not work I cannot get passed the security..... HELP I HAVE A VERY SEXY LAWN ORNIMATE thay id like to drive

 

[richardnewton]

Doesn't it need to be flashed to your VIN with a dealer computer or similar?

 

[RD_Atlanta]

It does need the VIN entered. If you don't have what you need to program the VIN, you can take it to a GM dealer and get your VIN programmed (I do my own but I've seen where they charge $150 to enter the new VIN). Just curious what was wrong with the original PCM?