Elog cheat discovery

[Waterloo]

We had issues with a 2002 Western Star like you are describing. The truck had a Qualcom unit at one time and the harness was left in the truck. It was the harness shorting out. One of the drivers that had some mechanical skills discovered it and removed the harness. The issues went away. Don't know if that helps, but that is where I would start, remove whatever was installed. See if you can get some wiring schematics for your T660 and start chasing, may have messed up one of the many canbus modules in the truck.