Well I think I finally figured out my problem.
My brother ordered a new V2 to OBDII cable last week.
Today while I was trying to scan a 2011 LML for the ECM serial number I was having the same error code. Troubleshooting led me to the V2 RJ45 connector. When I moved the cable it would cycle the V2 power.
Two of the pins, (#1, #2)were bent down and not touching fully to the cable. I tune my
LB7 more than any other vehicle. The
LB7 doesn't use the #2 pin but Can systems do.
I got a hold of Guy Tripp at SoCal diesel. He said not problem just send it in and he will take care of it.
Bob