Having same code. Motor and pump were changed out due to stripped splines. After new motor,pump install code 57 when request hydraulics. Hydraulics motor briefly work then codes out. Confirmed motor to controller connections and power feed/ fuses. No melting or oddities. Assume controller has bricked but can't see it working before new motor and pump were installed.

code 57 = Pump Motor Pulse Input Fault
result of fault is line contactor opened, pump contactor opened.

First off check all the fuses, check the controller connections.
Look for any burnt or melted areas around the U, V and W power cable connections.
Go to the pump motor and make sure it has not been contaminated by any battery acid spills from overcharging and battery overflow.
(i only mention this because i have ran into this before and since the pump motor is not protected very well acid spillover can get into the motor and destroy the sensor bearing causing failures).