Mercedes C219 CLS 320 CDI 224HP OM642.920 Engine ECU Kit A6421505526 Automatic

The Mercedes C219 224HP OM642.920 Engine ECU Kit A6421505526 Automatic is a complete engine control unit set designed for the diesel engine in the Mercedes C219 model with an automatic transmission. The kit comes from the Electronic Control Modules and Controllers group, ensuring component consistency within the engine control system. This solution is for users seeking a proven, used ECU module tailored to a specific powertrain configuration.

Specifications and technical data

• SKU: A6421505526-1
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6421505526
• Substitutable numbers: A6421505526, A 642 150 55 26, A2115452308, A 211 545 23 08, A0355657732, A 035 565 77 32, A0281014925, A 028 101 49 25
• Fuel type: Diesel
• Gearbox type: Automatic
• Part type: Engine Control Unit (ECU)
• Category: ECUs & Computer Modules

Application and System Configuration

The presented engine ECU kit is designed to work with the OM642.920 unit with 224 HP in the C219 body, powered by Diesel fuel. The controller is factory-intended to operate with an automatic transmission, which is crucial for proper communication with the transmission's mechatronics, traction control system, and other comfort and safety modules.

Selecting an ECU dedicated to a specific engine-transmission version minimizes the risk of adaptation issues, CAN network communication errors, and incorrect operation of functions such as kick-down, gear changes under load, or cold start strategy.

Technical Characteristics of the ECU Kit

The kit belongs to the Electronic Control Modules and Controllers group, meaning it is a central element for managing engine operating parameters. In practice, this translates to control over areas such as:

• fuel injection quantity and timing in a diesel engine,
• turbocharger pressure control and auxiliary equipment operation,
• coordination with the automatic transmission,
• OBD diagnostic functions and error logging.

The presence of dedicated replacement part numbers allows for precise matching of the controller to a specific vehicle equipment version, which is important when replacing within the same engine family.

Practical Application and Benefits of Installation

Choosing a used engine ECU kit for the Mercedes C219 with the OM642.920 unit is particularly beneficial in situations where:

• the original controller has suffered electronic or software damage,
• there are communication problems with the automatic transmission,
• a complete control unit replacement is necessary after a major powertrain failure.

A properly selected kit allows for the restoration of correct diesel engine operation, stable RPMs, proper starting, and predictable gear changes. For workshops specializing in the Mercedes brand, this is a practical service solution that reduces diagnostic time and the risk of incompatibility.

Integration with Vehicle Electronics

As an element from the Electronic Control Modules and Controllers group, the ECU kit communicates with other modules in the vehicle via communication buses. A correctly selected controller:

• ensures configuration consistency with safety and comfort systems,
• enables proper operation of diagnostic functions in service testers,
• facilitates subsequent software updates and service adaptations.

Therefore, installing such a kit is particularly recommended for vehicles where maintaining compatibility with the factory electronic architecture is important.

Technical Support and Additional Information

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 controllers, engine management modules, or auxiliary control units, check the available parts in the Mercedes Electronic Control Modules and Controllers category.

To better understand the operation of modern control modules and how to safely replace them using used parts, it is worth reading the guide on our blog: Years of Driving Pleasure – How to Care for iDrive Systems and Electronic Modules in BMW 3 and 5 Series Models. Although the description concerns a different brand, it discusses universal principles for handling vehicle electronics, which are also useful when working with ECUs in a Mercedes.

If you are considering further modifications to the engine unit's operating parameters using used components, the article Tuning with Used Parts – How to Gain Performance Without Losing a Fortune may also be helpful, as it discusses a safe approach to changes in vehicle electronics and mechanics.