Mercedes ECU & EIS Repair Services | Plug and Play Mail In Service

No, after a mail-in repair, the ECU or EIS should be fully functional upon return, and in most cases, it’s plug-and-play, allowing you to install the unit without needing to tow the vehicle.

Repairing a faulty ECU can enhance performance by restoring proper engine management. While EIS repairs won’t impact engine performance, they ensure reliable ignition and security functions.

Repair costs vary depending on the specific unit and the complexity of the repair. To obtain an accurate estimate:

1. Select Your Vehicle and Service: Choose your vehicle model and the specific service required on our website. We typically offer testing, repair, and replacement services.
2. Order the Testing Service: It's advisable to start with the testing service. If a repair or replacement is needed, the cost of the testing service will be deducted from your final bill.
3. Receive a Quote: After testing, we will either only charge you for a testing service, or upgrade the service to a repair or replace service. Any money paid towards the testing service will be credited to your final order.

Yes, please send the key, EIS, and ECU together. Having all three components allows us to fully test the primary systems required for starting the vehicle, ensuring thorough diagnostics and repair.

Yes, we can provide key programming solutions that allows the new key to function, even if all keys have been lost.

If we determine that your unit is irreparable, we will notify you, and you’ll have the option to choose a replacement or have the unit returned as-is. Units with extensive physical damage, water exposure, or evidence of tampering are typically beyond repair.

In most cases, our repair process ensures that the unit is ready for plug-and-play use when returned. In some limited instances, additional coding may be required. If reprogramming is necessary, our technician will inform you before completing the work to ensure you're prepared for any additional steps.

Before removing the ECU or EIS from your vehicle, use an OBD2 scanner to pull a detailed fault code report. We offer testing, repair, or replacement services for most products. It's best to start by ordering the testing service on our website. If a repair or replacement is needed, the cost of the testing service will be deducted from your final bill. You’ll also have the option to upload the fault code report to your support ticket for our reference.

We support all Mercedes models. If your ECU or EIS is not listed on the website, please contact us for assistance.

Signs of a faulty EIS include the key not turning, the car not recognizing the key, or the ignition failing to respond. If you experience any of these issues, the EIS likely needs attention.

Repair times vary but generally range from 1 to 5 business days, depending on the issue’s complexity and the repair process required.

Yes, we can reprogram or repair used Mercedes ECUs and EIS units, ensuring they are reconfigured for your specific vehicle, provided the module is compatible.

The ECU manages the engine's performance, optimizing fuel economy, controlling emissions, and adjusting various systems based on driving conditions to keep the engine running smoothly.

The ECU is usually located in the engine bay, often near the firewall, while the EIS module is found around the steering column, where the ignition switch is located. During checkout, we provide detailed instructions on how to locate the modules and remove them.

Common ECU issues include misfiring, engine stalls, and difficulty starting, while EIS faults often lead to ignition problems, where the key doesn’t turn or the car won’t start. Faults in either can also trigger warning lights on the dashboard.

No, an ECU (Engine Control Unit) manages the engine's performance and controls critical aspects like fuel injection and ignition timing, while an EIS (Electronic Ignition Switch) controls vehicle start authorization by validating the key and enabling the ECU.

Losing connection during programming can sometimes cause the ECU unit to lose communication with diagnostic tools, effectively locking the unit. In these cases, you have to reflash the ECU with the latest factory software to recover the unit. We can help restore proper functionality and communication with diagnostic systems.

Mercedes ECU/EIS programming involves configuring or reprogramming the Engine Control Unit (ECU) or Electronic Ignition Switch (EIS) to ensure they operate correctly with your vehicle’s specific system. This process is essential to ensure that all of your vehicle's parameters are accurately written to the EIS or ECU unit.