What would cause the heater fan to stay running when the vehicle is shut off 1989 caddy?

If the heater fan in a 1989 Cadillac continues to run after the vehicle is shut off, it could be due to a faulty ignition switch that fails to cut power to the fan. Another possibility is a malfunctioning relay or switch in the climate control system that keeps the fan activated. Additionally, a short circuit in the wiring could prevent the fan from shutting down. Checking these components can help diagnose the issue.