Hot waxes applied by automatic car washers have been known to affect the wiper's ability to clean windows.
To prevent damage to the wiper blades, do not use gasoline, kerosene, paint thinner, or other solvents on or near them.
When the wiper lever is in the AUTO position and the ignition is switched ON, the wipers may move automatically in the following cases:
If the windshield above the rain sensor is touched.
If the windshield above the rain sensor is wiped with a cloth.
If the windshield is struck with a hand or other object.
If the rain sensor is struck with a hand or other object from inside the vehicle.
Be careful not to pinch hands or fingers as it may cause injury, or damage the wipers. When washing or servicing the vehicle, make sure the wiper lever is in the OFF position.
Contamination of either the windshield or the blades with foreign matter can reduce wiper effectiveness. Common sources are insects, tree sap, and hot wax treatments used by some commercial car washes.
If the blades are not wiping properly, clean the window and blades with a good cleaner or mild detergent; then rinse thoroughly with clean water. Repeat if necessary.