Serial e216a027064 year 2009

Hi we have this yale that has Drive judders slowly. We thought encoder so replaced and still drives very slow then judders as we accelerate more. So thought possible faulty replaced encoder and ordered a genuine encoder from yale. Still same faukt.

Checked the 2 wires back from encoder to controller and they are both ok. Unfkrt6 do not have a wiring diagram to check all 4 wires back from encoder. Could someone please help with a wiring diagram or perhaps point me in the right direction as what it could be. I can only assume its either the motor or controller now However any advice would be greatly appreciated.

Thanks