Wiring Harness 2015 Chevrolet Silverado Windshield Washer Fluid Wiring A wiring harness is a system of wires that are bundled together and protected by a covering. Wiring harnesses are used in a variety of applications, including automotive, aerospace, and industrial. In the automotive industry, wiring harnesses are used to connect electrical components, such as lights, motors, and sensors, to the …