Yes, I checked the ALDL on the truck and all the pins and wires are fine. There are six in use on this truck. Right before I purchased it, the dealer re-flashed the BCM and fixed the cruise control and I was there. Ok, earlier today hooked the Tech2 with CANdi back up to our 2009 GMC Yukon XL and the splash screen (for lack of a better word) does not show the CANdi attached. The CANdi however, powers on, clicks and the green light flashes. If I set the Tech2 in bypass mode (enabled) I can get in to viewing data but the values such as actual RPMs are blank with a *. It will not recognize the CANdi at all, it is as if it is not even hooked up. Walking over to my 2004 Pontiac Montana, again the CANdi is still attached and does not show up on the splash screen. Setting the TECH2 to bypass mode allows me to see all engine functions in real time and I even reset two trouble codes (one of the reasons I bought this!). At this point I wonder if it is the adapter to the ALDL? The TECH2 will recognize the CANdi with the loop back connectors installed on the kitchen table and pass all tests. The 16-Pin adapter has 19 holes on the other side that attaches to either the TECH2 or CANdi. Two of those holes, 3 and 15 are not active, no connector in them. Not sure what to do at this point. Any ideas?