The ignition switch harness on a Ford Windstar is located
behind the steering column. You'll need to access it by removing or at least partially disassembling the lower steering column shroud. This involves removing screws and possibly some plastic trim pieces. The exact procedure varies slightly depending on the year of your Windstar.
Important Note: Working on the steering column and ignition system requires some mechanical aptitude. If you're not comfortable with this type of work, it's strongly recommended to take your Windstar to a qualified mechanic. Improperly working with the ignition system can be dangerous.
