Services
Control unit repair, diagnostics, coding – with a focus on Mercedes-Benz.
Control unit repair
Choose the affected system. We tell you whether a repair is possible after testing – clearly and before any work.
Typical: Starting problems, engine cuts out, limp mode, ECU fault codes
Describe starting problems, failures or other symptoms and list any fault codes. Whether the cause lies in the engine control unit is established during testing.
More on Engine control unitsTypical: Shifting problems, limp mode, transmission error messages
Describe shifting problems, error messages and when they occur. We agree diagnostics and repair steps with you for your specific vehicle.
More on Transmission control unitsTypical: ABS, ESP or brake warning light
List warning messages and any fault codes already read. For safety-relevant systems we clarify the cause and scope of testing before any work.
More on ABS & ESP control unitsTypical: Lighting, SAM modules, comfort functions fail
Describe failures, for example of lighting or comfort functions. We work out together which component is affected.
More on Comfort & body electronicsTypical: Speedometer, display or gauges fail
Describe display problems or failures as precisely as possible. Repair options are agreed after testing.
More on Instrument clustersTypical: Your control unit isn’t listed? Tell us the part number.
Give us the component name or part number. We first check whether we can work on your unit.
EnquireMercedes-Benz
Typical Mercedes parts we repair regularly – from the electronic ignition switch to the Direct Select module on the gearbox.
The electronic ignition switch (EZS) checks your key and enables the vehicle. If it fails, the Mercedes won’t start. We repair your original EZS.
Learn moreThe electric steering lock (ELV) on the steering column locks and unlocks the steering wheel. If it fails, the Mercedes can’t be started. We repair your original ELV.
Learn moreThe Direct Select Module (DSM) – formerly called Intelligent Servo Module (ISM) – sits on the gearbox and engages the selected gear, including the parking lock. We repair your original module.
Learn moreThe electronic selector lever module (EWM) detects which gear you select – P, R, N or D – and passes it on to the gearbox as a signal. We repair your original EWM.
Learn moreOn newer Mercedes models the FBS4 drive authorisation system protects control units, ignition switch and keys. A replacement or used part therefore doesn’t simply work. We adapt FBS4 control units to your vehicle.
Learn moreIf an engine or transmission control unit can no longer be repaired, we transfer the data from your original unit to a suitable replacement. The vehicle then recognises the new unit like the old one.
Learn moreKey lost, broken or you’d like a spare? We make a replacement key for your Mercedes and program it to match your vehicle.
Learn moreFault memory is only the start. We take symptoms, operating conditions and previous repairs into account – and tell you what is really faulty.
Request diagnosticsFailures, intermittent faults or implausible behaviour: describe when the fault occurs and what has already been done.
EnquireTell us the model, year and the change you want. We check technical feasibility before any order.
Convert an import vehicle to ECE / EuropeA separate section with a vehicle configurator and guide values.
Open the configuratorFocus on Mercedes-Benz. AEZ is an independent business; brand names are used for description only. The categories are no guarantee that every unit can be repaired.
