I'm trying to help out a local shop with a customers 2005 LLY. Long story short the customs ECM was having issues was sent off to get rebuilt. Couldnt be fixed so a new ECM was installed. After the new ecm was installed the shop installed the OS using the GM Global software. The shop then tried to reinstall the tunes but was not able to. He asked me for help to I hooked up to it and updated the autocal and was still not able to load the tunes. It gave me a $0533 error controller locked. I tried all the work arounds and still wouldnt load the tunes. So I hooked up to the truck with my flash scan and it wouldnt even let me read it with same error. We pulled the white buss bar under the dash and used a paper clip so that a direct connection was used to the ecm with no interference from the other controllers. Still would not let me read. The vin numbers on the ecm and the autocal match. Has anyone else had this issue?