2000 Audi S4 AutomaticFACTORY OEM SERVICE PROCEDURE

Generators & Regulators: Description

NOTE: Only wiring diagrams for S4 and are included in this article.

All models are equipped with Bosch 3-phase, self-rectifying, 90-amp, 110-amp, or 120-amp generator. See Figure . This internally-regulated generator is equipped with 14 diodes, with 3 exciter diodes connected to stator windings. These 3 diodes turn off the generator indicator light and supply power to the voltage regulator while the engine is running.

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.