The power fo the winch comes directly from the battery thru two circuit breakers connected in parallel. They are connected to the positive post on the battery. The elec diagram for the winch shows a fuse at the winch but on my 2805C it is not there. I think HiLo used the circuit breakers instead of the fuse. The breakers protect the wire as well as the winch motor. Make sure there is power thru the circuit breakers. They are just auto type breakers and can be gotten at any auto parts store. If you have power thru them then look for the loose connection. Also on my winch, the plate that trips the two limit switches that stop the motor has stripped out and does not move. I know when to stop the motor with the control switch. If your plate has stripped out at a position that has one of the limit switches in the open position you would not have power to the motor.
Jim L & Faye
2003 Silvarado diesel crew cab
2017 Silvarado, crew cab 1500 6.2L gas w/ 8 speed tranny