Trans issue

I just got finished doing head gaskets on my lly and as I was pulling truck out of the shop the Trans went into limp mode. I scanned it an pulled a p0872 code. Open circuit. I dropped pan ohmed the solenoid and found I have a open circuit for the e-shift solenoid wire. Anyone Ever come across this issue? I'm going to start tracing wires back now looking for a bad connection or broken wire. Any Info would be greatly appreciated thanks