Power commander 3 not working

[Mustang]

Have you connected the earth wire and got a good earth?
Check the the connector between the bikes loom and the power commander, mine were quite hard to get fully seated together correctly.

Also I have heard that the 9V battery needs to be new for it to give the necessary voltage.

Done all that, new 9.56 v battery.....pc lights stay on ok, usb plugs in and pings on the laptop but no comms.