The Audi A4, produced for the 2001 model year, represents the post-facelift B5 generation, known for its refined styling, solid build quality, and the availability of Audi's legendary Quattro all-wheel-drive system. This compact executive sedan and wagon offered a choice of efficient and powerful engines, including 1.8L turbocharged inline-fours and a 2.8L V6, competing with established luxury marques like BMW and Mercedes-Benz. Its design emphasized clean lines and premium appointments, reflecting Audi's commitment to engineering excellence and a sophisticated driving experience.

This comprehensive Electrical Service Manual and Wiring Diagrams provides detailed technical information for the Audi A4 (B5, post-facelift). Covering all vehicle electrical systems, it includes diagnostic procedures, troubleshooting charts, component replacement instructions, and high-resolution wiring diagrams essential for maintenance and repair. The manual is designed for owners, mechanics, and technicians in North America and Europe, offering advanced diagnostic capabilities and circuit tracing information to ensure the optimal performance and longevity of your vehicle.