Bosch AL0831N Alternator

Bosch AL0831N Alternator Overview

The Bosch AL0831N is a new 14-volt alternator built for charging-system service on select Audi and Volkswagen applications. It features a 150-amp amperage rating, internal regulation, clockwise rotation, and a 6-groove pulley for belt-driven operation.

Bosch Premium Alternators are engineered, built, and tested for consistent electrical output and dependable operation. The AL0831N is a direct-fit replacement for vehicles originally equipped with Bosch or Valeo units in the listed applications, including Audi A4, Audi A4 Quattro, Audi A6, Audi A6 Quattro, Allroad Quattro, and Volkswagen Passat.

• 14-volt alternator with 150-amp output
• Internal regulator and internal fan design
• Clockwise rotation
• 6-groove pulley included
• Aluminum case and aluminum housing construction
• Plug type 364 with rear-view plug clocking at 6 o’clock
• New Bosch alternator, part number AL0831N

Detailed Product Information

The Bosch AL0831N alternator is designed for charging-system replacement where the original unit matches the listed Bosch or Valeo configurations. It is a new alternator with a 64 mm outside pulley diameter, internal voltage regulation, and an external fan included for thermal management. The aluminum case helps keep the unit lightweight while maintaining the fit and mounting characteristics expected in OE-style service parts. If you are replacing a failing alternator on an Audi A4, Audi A4 Quattro, or Volkswagen Passat, AL0831N provides the electrical output and mounting details needed for the specified applications.

This part cross-references Bosch and OE-style applications for the same vehicle coverage, including 06C903016B and 078903016AC.

Common Problems This Part Can Help Solve

• Battery warning light caused by alternator output loss
• Low charging voltage at idle or under electrical load
• Dim lights, slow accessory operation, or intermittent electrical performance
• Charging-system failure from worn internal components
• No-charge condition after alternator wear or bearing failure

Installation Notes and Fitment Tips

Compatible With 2002-2005 Audi A4, with Bosch unit; 2002-2004 Audi A4, with Valeo unit; 2004 Audi A4 Quattro, with Bosch or Valeo unit; 2002-2005 Audi A4 Quattro, with Bosch or Valeo unit; 2002-2004 Audi A6, with Bosch unit; 2002-2004 Audi A6 Quattro, with Bosch or Valeo unit; 2002-2005 Audi Allroad Quattro, with Valeo unit; and 2003-2005 Volkswagen Passat, with Bosch or Valeo unit, as listed in the fitment data.

• Verify the original alternator brand, amperage rating, and plug clocking before installation.
• Confirm pulley style and belt alignment match the vehicle’s existing setup.
• Check charging-system wiring, battery condition, and belt drive components during replacement.
• Use the vehicle-specific fitment notes for chassis breakpoints and alternator type selection.

Quality Assurance

Bosch Premium Alternators are built and tested to support reliable charging-system performance. The AL0831N is a new alternator designed to meet the fitment and electrical requirements listed for the covered Audi and Volkswagen applications.