Bosch SR0509X Starter

Bosch SR0509X Starter Overview

The Bosch SR0509X is a remanufactured 12-volt starter built for dependable engine cranking in select Mercedes-Benz applications. It is engineered with a grounded aluminum case, aluminum nose cone, and attached solenoid for a direct replacement solution on vehicles with automatic start/stop systems.

Compatible With Mercedes-Benz GLA250, CLA250, CLA45 AMG, GLA45 AMG, and B250 applications across the listed model years, this Bosch starter supports OE-style fitment and consistent starting performance. The SR0509X part number is also a useful reference when verifying the correct replacement starter for your vehicle.

Key Features

• 12-volt remanufactured starter for Mercedes-Benz starting systems
• 1.95 power rating for OE-style cranking performance
• Counterclockwise (left) rotation
• Grounded case design with aluminum housing and aluminum nose cone
• Attached solenoid for streamlined replacement
• Flange mount design with 2 mounting bolt holes
• Designed for automatic start/stop operation
• Remanufactured Bosch starter, part number SR0509X

Detailed Description

Bosch Premium Starters are remanufactured, built, and tested to deliver reliable performance in demanding starting applications. The SR0509X uses a flange mount layout, grounded case construction, and counterclockwise rotation to match the requirements of the listed Mercedes-Benz vehicles. Its aluminum components help keep weight down while maintaining the structural characteristics needed for consistent starter engagement.

This starter is a strong match for drivers searching for a remanufactured starter for 2013-2020 Mercedes-Benz B250, 2014-2019 Mercedes-Benz CLA250, 2014-2019 Mercedes-Benz CLA45 AMG, 2015-2019 Mercedes-Benz GLA45 AMG, and 2015-2020 Mercedes-Benz GLA250. If you are replacing a worn starter on a Mercedes-Benz GLA250 or CLA250, the Bosch SR0509X provides a direct-fit option built around the original application requirements.

This part cross-references Bosch OE numbers 2709060700 and 6459060800 for the same application.

What This Starter Helps Solve

• Slow or weak engine cranking
• No-start conditions caused by starter wear
• Intermittent starting after repeated key cycles
• Starter noise from worn internal components
• Starting issues on vehicles equipped with automatic start/stop systems

Installation Notes and Tips

Verify the vehicle’s original starter configuration before installation, including 12-volt system requirements, counterclockwise rotation, flange mount style, and the 2-bolt mounting pattern. This starter does not include mounting hardware or shims, so reuse or source the correct hardware as needed. Confirm electrical connections, solenoid alignment, and clearance around the starter housing before tightening fasteners.

For best results, inspect the battery, charging system, and engine ground connections during replacement. A weak battery or poor ground can mimic starter failure and affect the performance of a new unit.

Quality Assurance

Bosch remanufactured starters are produced and tested to meet application-specific performance and reliability expectations. The SR0509X is built for the listed Mercedes-Benz fitments and reflects Bosch’s focus on controlled remanufacturing and functional verification before release.

• Brand: Bosch
• Part Number: SR0509X
• Type: Starter, remanufactured
• Voltage: 12V
• Mounting Type: Flange