Can a winch run on a DC regulated power supply?
No, cannot use a transformer or power pack, they do not have the amperage required to power the winch properly.
If one was used and the winch stopped working the winch will need to be tested to make sure it is still in good and in useable service. Hook the winch up to a 12-volt battery with the circuit breaker inline as described in the owner’s manual, if the winch does not operate, remove the circuit breaker for testing to verify and eliminate the chance the breaker could be a problem.