My daughter had a CEL on her 2005 Equinox..... I plugged in my Launch Scanner to it and it kept coming back as "No ECM found...." So I plugged in another scanner to find out the source of the CEL and it worked just fine. I plugged the Launch tool into other cars and it worked just fine.....then I plugged it back into the Equinox and once again I got the "No ECM found"....... other cars work just fine with the Launch..... other Diagnostic Tools work just fine on the Equinox........ what gives??

Get hold of Launch.
They may have a patch.

Weird. It looks like it should be software updatable so maybe it needs an update? I suspect the "No ECM Found" is the error it comes up with when it tries to talk to it and doesn't recognize something that her Equinox says.