Mercedes W169 W245 Glow Plug Relay Unit Module OM640 Diesel Engine A6409004200

The Mercedes W169 W245 OM640 Glow Plug Controller is a specialized module designed for the fuel systems of diesel engines in Mercedes compact class vehicles. It is responsible for precise control of glow plug operation, which translates to stable engine starting and proper operation during the warm-up phase.

Specifications and technical data

• SKU: A6409004200
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6409004200
• Substitutable numbers: A6409004200, A 640 900 42 00, KZ
• Fuel type: Diesel
• Category: Glow Plugs

Purpose and Role in the Diesel System

The glow plug controller in a Diesel engine is responsible for controlling the duration and intensity of glow, adjusting parameters to the engine temperature and operating conditions. For OM640 units installed in Mercedes W169 and W245, a correctly functioning control module is crucial for:

• reliable cold starts,
• reducing smoke during the initial operating phase,
• minimizing mechanical and thermal stress on the engine,
• maintaining correct combustion parameters.

Thanks to its dedicated design, the controller integrates with the vehicle's electronics, ensuring consistency with the factory fuel system architecture.

Technical Characteristics and Compatibility

The presented controller belongs to the glow plugs category in terms of the hardware controlling their operation. It is a component designed to work with diesel engines requiring precise control of the combustion chamber preheating phase.

The module has an assigned OEM part number and related interchangeable numbers, which facilitates the selection of the appropriate variant for a specific vehicle configuration. This allows for a technically correct fit of the controller to the electrical system and engine without the need for wiring or software modifications.

Condition, Origin, and Benefits of Use

The offered controller comes from the Mercedes brand and is a used part, allowing for an economical repair of the glow system while maintaining the original manufacturer's specifications. Choosing a dismantled module is a solution that in many cases enables:

• reducing service costs compared to purchasing a new component,
• maintaining compatibility with the vehicle's factory electronics,
• preserving the original operating characteristics of the starting system.

A properly selected glow plug controller helps eliminate typical fault symptoms such as extended starting, uneven cold running, or error messages related to the glow system.

Benefits of Installation in Mercedes W169 / W245

Using a dedicated controller in Mercedes W169 and W245 models with the OM640 engine brings a range of practical operational benefits:

• more predictable vehicle behavior in low temperatures,
• reduced risk of glow plug damage due to incorrect control,
• increased user comfort thanks to efficient starting,
• maintaining operating parameters in line with manufacturer's specifications.

For workshops and individual users, this means the possibility of efficient repair of the glow system without interfering with other engine components.

Mercedes Glow Plugs – Selection and Extended Offer

If you are looking for other components from the Mercedes glow plugs category for your vehicle, check out our dedicated offer: Mercedes glow plugs. You will find a wide selection of components related to the glow system there, which will facilitate comprehensive service maintenance.

For a comparison of strategies for saving on car parts, you can also read a guide on economical repair of popular models, available here: how to save on original car parts. This is a practical addition to your knowledge when planning your vehicle service budget.