WAI 20741N Alternator

WAI 20741N Alternator Overview

The WAI 20741N alternator is a 150 amp, 100% new replacement built for modern electrical demand. It is engineered with an internal fan, internal regulator, and a decoupled clutch pulley to support stable charging performance in Mercedes-Benz applications.

Compatible with Mercedes-Benz GLA250, Mercedes-Benz B250, and Mercedes-Benz CLA250 applications, this alternator is built on the BOSCH family platform and uses a serpentine belt drive with a 5-groove pulley. The WAI 20741N is a direct-fit charging component for vehicles that require reliable alternator output and clockwise rotation.

Key Features

• 150 amp amperage rating for higher electrical load support
• 100% new unit, not remanufactured
• Internal fan and internal voltage regulator
• Clockwise (right) rotation
• Pulley included with 5-groove serpentine belt design
• Decoupled or clutch pulley design
• BOSCH family alternator construction

Detailed Description

WAI 20741N is an alternator replacement for 2013-2019 Mercedes-Benz B250, 2014-2019 Mercedes-Benz CLA250, and 2015-2020 Mercedes-Benz GLA250 applications. It is built to deliver the amp output needed for vehicle charging systems that power lighting, electronics, climate controls, and other onboard loads. The 12-volt design, internal regulation, and pulley configuration make it a practical OE-style replacement for vehicles using this charging system layout. This part number, 20741N, is also referenced in cross applications such as Dorman - HELP 20741 for the same application.

Common Problems This Part Can Address

• Battery warning light caused by alternator output loss
• Low charging voltage during driving or idle conditions
• Electrical system instability from a failing charging unit
• Dim lights or weak accessory performance tied to charging issues
• Noise or pulley-related charging system concerns

Installation Notes and Tips

Verify pulley type, groove count, rotation direction, and regulator style before installation. Confirm vehicle-specific fitment for your Mercedes-Benz GLA250, B250, or CLA250 application and inspect the serpentine belt, belt tensioner, and charging connections during replacement. Proper electrical testing after installation helps confirm charging system performance.

Quality Assurance

WAI states that this alternator is manufactured as a 100% new unit using proprietary components and processes to support long service life and consistent performance. The 20741N part number is built for charging-system replacement in confirmed Mercedes-Benz fitments.