Mercedes W169 W245 A B 160 180 200 CDI OM640 Alternator Generator A6401540502

Visual condition of the part

The product shows signs of use visible in the photos.

Mercedes W169 W245 A B 160 180 200 CDI OM640 Alternator is an original component from the Alternators and generators group, designed for the OM640 series diesel engines. This used part ensures factory-fit compatibility with the electrical system, which facilitates maintenance and reduces the risk of battery charging issues.

Specifications and technical data

• SKU: A6401540502-1
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6401540502
• Substitutable numbers: A6401540502, A 640 154 05 02
• Fuel type: Diesel
• Category: Alternators & Generators

Application and compatibility with the OM640 unit

The presented alternator has been designed to work with the Diesel OM640 series engines used in A-Class and B-Class models. The design, adapted to the characteristics of the diesel unit, ensures stable charging across the entire RPM range, even under high electrical load (lighting, heating, onboard electronics).

Thanks to the preservation of factory mounting geometry and the correct drive ratio, the alternator works with the engine accessory system without the need for modifying brackets or belt routing. This solution is particularly beneficial when servicing vehicles used intensively in urban traffic.

Construction and operating parameters of the alternator

The alternator from this series belongs to the Alternators and generators group, meaning it is responsible for generating electrical energy for all vehicle systems and recharging the battery. The rotor and stator design is optimized for operation in diesel engines, which generate high torque even at low RPMs.

In practice, this translates into:

• efficient battery charging during city driving and short trips,
• stable supply voltage for control units and safety systems,
• adequate power reserve for additional electrical consumers.

The original construction ensures proper cooling and resistance to thermal loads typical of a diesel engine bay, which is important for the durability of the entire charging system.

Condition, origin, and benefits of choosing a used alternator

The offered alternator is a used part, which allows for combining a reasonable purchase cost with the preservation of the manufacturer's factory specifications. For many users, this means the ability to restore full functionality to the charging system without the need to invest in expensive replacements with uncertain parameters.

Choosing an original, used alternator for a diesel engine brings a number of practical advantages:

• factory fit for the vehicle's electrical and mechanical installation,
• preservation of the operating characteristics intended by the manufacturer,
• reduced risk of compatibility issues with control units and onboard systems.

Why choose an original Mercedes alternator

The alternator dedicated to OM640 units in A-Class and B-Class models was developed with the specific requirements of diesel engines in mind. Properly selected charging characteristics support reliable starting, stable operation of electronics, and longer battery life, which has a direct impact on the comfort of daily use.

For workshops and individual users, this means:

• easier diagnostics and maintenance of the charging system,
• lower risk of complaints related to incorrect part selection,
• consistency with the vehicle manufacturer's technical documentation.

If you are planning a comprehensive repair or upgrade of the engine area in your Mercedes and need other components from the same group, such as alternators with different capacities, auxiliary generators, or related mounting elements, check the available parts in the Mercedes alternators and generators category.

For a broader perspective on the use of dismantled parts in vehicle repairs, including post-collision work and the selection of original components, it is worth reading the guide Bodywork and chassis – post-accident repairs using dismantled parts, which discusses the practical aspects of using used OEM parts.