I guess I didn't express myself clearly. I didn't mean to imply Adam would get codes. I meant that I had a code that very well may have been related to the harness as much as the solenoid. The harness could fray or harden. This could end up being a gremlin for Adam's install. I realize he's wiring this independent from the XK's computer.
I'm not sure this was any clearer than before!