how to fix 1986 beauvill van power window

Pull door panel, w a test light and verify that voltage is present flip switch up/down positions see if voltage switches. If it doesnt switch (voltage in but not out the switch is junk. If all checks out then the window motor needs replaced. Some models are pop riveted in and can be a challenge even for seasoned techs. I do not know your back ground on repairs - c-15 van doors. Hope that helps