I've just fitted an owned (in good condition) window regulator to my 1999 e39 525' once fitted I reconnected the battery to test the regulator, however it didn't work as I thought, power was getting to the regulator but no output, then it started to smoulder like something was burning. Being an electrician I thought the motor was jammed in one position. Would that be the fault or has anyone an idea as to what and how to fix this.