1970, Now that you have access to the swift wizard I would set a trigger for your fault and watch the frames, compare your Velocity between DPP and Encoder. I had an intermittent issue on a Swift Meridia where the car would lose position for a split second and the car would just stop or position would be completely wrong. I replaced the selector boards and checked voltage between both DPPs, car would still lose position. I eventually replaced DPP sensors, swapped Shielded pairs in case of a traveler issue and ran the car, fixed my issues. Hope this helps