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).