Mercedes W169 W245 M266 Petrol Engine Wiring Harness Loom A2661503033

Mercedes W169 W245 M266 Petrol Engine Wiring Harness Loom is a factory-original, used electrical harness designed for petrol-powered engines in Mercedes A-Class and B-Class models. This component is responsible for the precise connection of sensors, auxiliary equipment, and the engine control unit, ensuring stable communication throughout the powertrain. It is an ideal solution for users seeking a well-fitted, original installation for professional repairs or the replacement of a damaged harness.

Specifications and technical data

• SKU: A2661503033
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2661503033
• Substitutable numbers: A2661503033, A 266 150 30 33, A2661501833, A 266 150 18 33, A2661501433, A 266 150 14 33, A2661500633, A 266 150 06 33, BG
• Fuel type: Petrol
• Category: Wiring Harnesses, Cables & Connectors

Purpose and function in the engine system

The presented engine wiring harness is designed to work with the M266 unit in Mercedes A-Class (W169) and B-Class (W245) cars with petrol engines. It is responsible for distributing power and control signals between key auxiliary components, such as sensors, actuators, and the engine control unit. A properly selected harness allows for the restoration of correct ignition and injection system operation, eliminating electrical communication issues and errors stored in the controller's memory.

Benefits of using an original harness

Using an original engine wiring harness in a Mercedes W169 or W245 ensures:

• factory-perfect fit of wire lengths and connectors for the M266 unit,
• proper wire routing in the engine bay, consistent with factory mounting points,
• correct placement of connectors for sensors and actuators,
• maintenance of electrical parameters required by the engine control unit,
• reduction of the risk of starting problems, rough engine operation, or sporadic installation errors.

As a result, the harness is a practical solution for replacing a damaged installation, post-collision repairs, or restoring full powertrain efficiency in petrol-powered vehicles.

Technical characteristics and compatibility

The harness belongs to the Wires, harnesses, and connectors category, meaning it includes a set of wires with factory connectors adapted to a specific engine system. The design is intended for operation in the engine bay, taking into account the elevated temperatures and vibrations characteristic of petrol units. The product has an assigned OEM part number and associated interchangeable numbers, which facilitates verification of compatibility with a specific vehicle configuration in manufacturer catalogs or parts selection systems.

Before installation, it is recommended to compare the shape, connector layout, and branch configuration with the removed harness to confirm full compatibility with the specific vehicle equipment version. This approach minimizes installation time and reduces the risk of needing to modify the wiring.

Practical application and installation

The engine wiring harness in the Mercedes W169/W245 is a key component for:

• replacing a damaged or melted installation in the engine bay,
• repairs after electrical short circuits in the engine area,
• engine swaps within the same family of petrol units,
• diagnosing and eliminating communication problems between sensors and the controller.

Professional installation involves routing the harness according to factory paths, using original mounting points, and securely plugging in all connectors. A properly installed harness maintains the stability of electrical parameters and facilitates subsequent service diagnostics.

Product condition and operational safety

The offered harness is a used item, which in practice means it has been removed from a vehicle and verified for further use. In the case of an engine harness, it is particularly important to check the integrity of the wire insulation, the condition of the connectors, and the absence of mechanical damage that could affect the stability of electrical connections. Choosing this solution allows for an economical repair while maintaining the factory concept of the electrical system in Mercedes A-Class and B-Class cars with petrol engines.

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 additional harnesses, sensor wires, or service connectors, check the available parts in the Mercedes Wires, harnesses, and connectors category.

For drivers interested in a broader approach to the safe selection of used components in vehicle systems, the guide article Second-hand braking system: how to safely choose discs, calipers, and ABS? may be helpful, as it shows what to look for when purchasing parts from the secondary market.