[pestes]

Drove out of Shendoah River State Park this morning and noticed right away that my tach was bouncing back and forth between 0 and max with "test" on the LCD display just like it normally does when I start the engine. Except it literally did this all day long. Tach is correct on the VMSpc so I suspect something between dash and rear. It worked when we pulled in 5 days prior. Of note, I did have the dash off when parked for the week to mount the VMSpc tablet but I never had my hands anywhere near the instrument cluster. Does the tach connect all the way to the rear? Or does it go to the Allison computer under the driver?