The multi-function switch in the Ford Mustang controls the windshield wipers, turn signals and dimmer switch. When one of the components in this switch fails, then the entire switch should be replaced. Replacing the switch will only take a matter of minutes. The switch is located on the steering column so getting to it is a matter of removing the steering column shroud cover.
Open the hood to access the battery. Disconnect the negative battery terminal with a crescent wrench to isolate the electricity.
Unscrew the steering wheel console shroud with a Phillips head screwdriver. You may have to tilt the steering wheel to make the shroud easier to remove.
Unsnap the wiring harness from the back of the switch. The connector has tabs that can be pulled away to separate the harness from the switch.
Unscrew the switch from the steering column with a Phillips head screwdriver. The switch will come out freely from the column.
Place the new switch on the steering column where the old one was.
Install the screws to the holes with a Phillips head screwdriver.
Click the wiring harness into the connector. The harness will snap into place.
Place the shroud back around the steering wheel. Tighten with a Phillips head screwdriver. You may have to adjust the steering wheel for a better fit.
Connect the negative terminal back to the battery with a crescent wrench. Close the hood.
Start the vehicle to test the switch. Test the turn signals, windshield wipers and the high beams.
