'09 LMM 3500 dually. Previous owner had a 5 position switch installed, along with EGR and DPF deleted - physically and within the EFI live tune.
See attached. I can read the Allison just fine it seems, but I'm wondering if the 5 position switch that's installed is getting in the way of me reading the E35b? I've tried reading from each of the 5 positions and each time failure.