attempted to read a customers LS Swap 2010 Silverado 5.3 E38 and I keep getting Protocol Failure message. I attempted to hook up to my personal truck E67 ECU and had not issues, worked as advertised. I also swapped out the E38 ECU with a known good spare and got the same failure message. I attempted the resync and it didn't fix anything.
How do manually push a firmware update?
Could it be a wiring issue with the LS swap truck? only needs constant power to PSI conversions harness (starter wires) and cranking power, easily found in fuse panel. So wiring is straight forward and not a hack job, all professionally done with good products.
I submitted a ticket (228943) but highly doubt its my interface as it reads fine on one vehicle and not another. Anyone else run into a vehicle specific issue not allowing hook up?