The Audi S4 name was originally used for the high performance sport version of the Audi 100 car and has subsequently been used for similar versions of the Audi A4 series. Like most Audi S cars, the S4 is only available with Audi’s quattro four-wheel drive (4WD) system, with the S4 utilizing the Torsen-based permanent “full-time” 4WD.
The following Wiring Diagrams and Electrical System Schematics apply for Audi S4 2001 model year. Here you will find complete diagrams, illustrations, and description of the electrical system, components, parts, connectors of the S4 which include Anti-lock Brakes System (Quattro, EDL, ESP), Airbag Control Module, Battery, Starter and Generator, Climate Control System, Cluster, Oil pressure, Fuel Pump and Oil Level Circuit Diagram, Driver Information System, ECU, Coils and Fuses, Emergency Switch Relay Lights, Fuse Box, Instrument Cluster, Cruise Control System, Navigation System, Stereo Bose and CD Changer, Windshield Wiper Switch Pump Motor Relay, etc.
Find more information about Audi S4 Wiring Diagrams and Electrical System Schematics here. (source: boom.net)