[Jukebox-list] Seeburg STD 4 Problem

Working on the old "scans Twice doesnt pick up a record " problem.  Going by the "symptom 3   troubleshooting guide.  The write in voltage at the DCC reads @ 120 Vdc, but I dont see a drop when I make a selection. The guide mentions the write-in trigger. Seems like I dont have that trigger. Anyone else ever experience this ?